Process for the preparation of (mercaptoorganyl)-alkoxysilanen

The invention relates to a process for the preparation of (mercaptoorganyl) alkoxysilanes.

GB 1 102 251 discloses the reaction of alkali hydrogen sulfides with (haloalkyl) alkoxysilanes in methanolic medium to give the corresponding (mercaptoalkyl) alkoxysilanes at normal pressure. A disadvantage of this procedure is the extraordinarily long reaction time (96 h) in order to achieve high conversion rates and the unsatisfactory yield achieved in the process.

It is known (mercaptoalkyl) alkoxysilanes by the reaction of alkali hydrogen sulfide with suitable (haloalkyl) alkoxysilanes in the presence of a 10-100% molar excess of H.₂S manufacture (US 5,840,952). This process has the disadvantage on an industrial scale that highly toxic H₂S has to be stored, dosed and handled and the process is carried out in two stages, whereby the space-time yield of the process basically decreases.

It is also known to produce (mercaptoalkyl) alkoxysilanes by reacting (haloalkyl) alkoxysilanes with alkali hydrogen sulfide (NaSH) in polar, aprotic solvents (EP 0 471 164). The disadvantage of the process is that large amounts, at least 50% by volume, of solvent are used and this is toxic, for example in the case of dimethylformamide. In addition, the high boiling point of dimethylformamide makes it difficult to work up and purify the reaction products later by distillation.

The object of the invention is to provide a process for the preparation of (mercaptoorganyl) alkoxysilanes which, while avoiding the storage, metering and supply of highly toxic hydrogen sulfide or toxic dimethylformamide, enables short reaction times and thus high space-time yields with good selectivity during the reaction the (Halogenorganyl) silanes enables.

The invention relates to a process for the preparation of (mercaptoorganyl) alkoxysilanes, which is characterized in that alkali metal hydrogen sulfide is reacted with a mixture of (halogenorganyl) alkoxysilane and (halogenorganyl) halosilane in an alcohol in a closed vessel with the exclusion of air and at elevated pressure .

(Mercaptoorganyl) alkoxysilanes can compounds of the general formula I.

<chemistry id="chem0001" num="0001"><img file="EP1538152B1_D0001.tif" /></chemistry>be where R the same or different and an alkyl, preferably CH₃, Alkenyl, aryl or aralkyl group with C₁-C₈ or is an OR 'group R 'the same or different and a C₁-C₂₄ , preferably C₁-C₄ or C₁₂-C₁₈is branched or unbranched monovalent alkyl or alkenyl group, aryl group or aralkyl group, R '' is a branched or unbranched, saturated or unsaturated, aliphatic, aromatic or mixed aliphatic / aromatic divalent C₁-C₃₀ Hydrocarbon group, optionally with F-, Cl-, Br-, I-, NH₂-, or NHR 'is substituted, x is 1-3.

For x = 1, R '' -CH₂-, -CH₂CH₂-, -CH₂CH₂CH₂-, -CH₂CH₂CH₂CH₂-, -CH (CH₃) -, -CH₂CH (CH₃) -, -CH (CH₃) CH₂-, -C (CH₃)₂-, -CH (C₂H₅) -, -CH₂CH₂CH (CH₃) -, -CH₂CH (CH₃) CH₂- or<chemistry id="chem0002" num="0002"><img file="EP1538152B1_D0002.tif" /></chemistry>mean.

For x = 2, R '' CH, -CH-CH₂, -CH₂-CH, -C-CH₃, -CH-CH₂-CH₂, -CH-CH-CH₃ or -CH₂-CH-CH₂ mean.

(Mercaptoorganyl) alkoxysilanes of the general formula I can be:

<ul id="ul0001" list-style="none" compact="compact"><li>3-mercaptopropyl (trimethoxysilane),</li><li>3-mercaptopropyl (triethoxysilane),</li><li>3-mercaptopropyl (diethoxymethoxysilane),</li><li>3-mercaptopropyl (tripropoxysilane),</li><li>3-mercaptopropyl (dipropoxymethoxysilane),</li><li>3-mercaptopropyl (tridodecanoxysilane),</li><li>3-mercaptopropyl (tritetradecanoxysilane), '</li><li>3-mercaptopropyl (trihexadecanoxysilane),</li><li>3-mercaptopropyl (trioctadecanoxysilane),</li><li>3-mercaptopropyl (didodecanoxy) tetradecanoxysilane,</li><li>3-mercaptopropyl (dodecanoxy) tetradecanoxy (hexadecanoxy) silane,</li></ul><ul id="ul0002" list-style="none" compact="compact"><li>3-mercaptopropyl (dimethoxymethylsilane),</li><li>3-mercaptopropyl (methoxydimethylsilane),</li><li>3-mercaptopropyl (diethoxymethylsilane),</li><li>3-mercaptopropyl (ethoxydimethylsilane),</li></ul><ul id="ul0003" list-style="none" compact="compact"><li>3-mercaptopropyl (dipropoxymethylsilane),</li><li>3-mercaptopropyl (propoxydimethylsilane),</li><li>3-mercaptopropyl (diisopropoxymethylsilane),</li><li>3-mercaptopropyl (isopropoxydimethylsilane),</li><li>3-mercaptopropyl (dibutoxymethylsilane),</li><li>3-mercaptopropyl (butoxydimethylsilane),</li><li>3-mercaptopropyl (diisobutoxymethylsilane),</li><li>3-mercaptopropyl (isobutoxydimethylsilane),</li><li>3-mercaptopropyl (didodecanoxymethylsilane),</li><li>3-mercaptopropyl (dodecanoxydimethylsilane),</li><li>3-mercaptopropyl (ditetradecanoxymethylsilane),</li><li>3-mercaptopropyl (tetradecanoxydimethylsilane),</li></ul><ul id="ul0004" list-style="none" compact="compact"><li>2-mercaptoethyl (trimethoxysilane),</li><li>2-mercaptoethyl (triethoxysilane),</li><li>2-mercaptoethyl (diethoxymethoxysilane),</li><li>2-mercaptoethyl (tripropoxysilane),</li><li>2-mercaptoethyl (dipropoxymethoxysilane),</li><li>2-mercaptoethyl (tridodecanoxysilane),</li><li>2-mercaptoethyl (tritetradecanoxysilane),</li><li>2-mercaptoethyl (trihexadecanoxysilane),</li><li>2-mercaptoethyl (trioctadecanoxysilane),</li><li>2-mercaptoethyl (didodecanoxy) tetradecanoxysilane,</li><li>2-mercaptoethyl (dodecanoxy) tetradecanoxy (hexadecanoxy) silane,</li></ul><ul id="ul0005" list-style="none" compact="compact"><li>2-mercaptoethyl (dimethoxymethylsilane),</li><li>2-mercaptoethyl (methoxydimethylsilane),</li><li>2-mercaptoethyl (diethoxymethylsilane),</li><li>2-mercaptoethyl (ethoxydimethylsilane),</li></ul><ul id="ul0006" list-style="none" compact="compact"><li>1-mercaptomethyl (trimethoxysilane),</li><li>1-mercaptomethyl (triethoxysilane),</li><li>1-mercaptomethyl (diethoxymethoxysilane),</li><li>1-mercaptomethyl (dipropoxymethoxysilane),</li><li>1-mercaptomethyl (tripropoxysilane),</li><li>1-mercaptomethyl (trimethoxysilane),</li><li>1-mercaptomethyl (dimethoxymethylsilane),</li><li>1-mercaptomethyl (methoxydimethylsilane),</li><li>1-mercaptomethyl (diethoxymethylsilane),</li><li>1-mercaptomethyl (ethoxydimethylsilane),</li></ul><ul id="ul0007" list-style="none" compact="compact"><li>1,3-dimercaptopropyl (trimethoxysilane).</li><li>1,3-dimercaptopropyl (triethoxysilane),</li><li>1,3-dimercaptopropyl (tripropoxysilane),</li><li>1,3-dimercaptopropyl (tridodecanoxysilane),</li><li>1,3-dimercaptopropyl (tritetradecanoxysilane),</li><li>1,3-dimercaptopropyl (trihexadecanoxysilane),</li></ul><ul id="ul0008" list-style="none" compact="compact"><li>2,3-dimercaptopropyl (trimethoxysilane),</li><li>2,3-dimercaptopropyl (triethoxysilane),</li><li>2,3-dimercaptopropyl (tripropoxysilane),</li><li>2,3-dimercaptopropyl (tridodecanoxysilane),</li><li>2,3-dimercaptopropyl (tritetradecanoxysilane),</li><li>2,3-dimercaptopropyl (trihexadecanoxysilane),</li></ul><ul id="ul0009" list-style="none" compact="compact"><li>3-mercaptobutyl (trimethoxysilane),</li><li>3-mercaptobutyl (triethoxysilane),</li><li>3-mercaptobutyl (diethoxymethoxysilane),</li><li>3-mercaptobutyl (tripropoxysilane),</li><li>3-mercaptobutyl (dipropoxymethoxysilane),</li><li>3-mercaptobutyl (dimethoxymethylsilane),</li><li>3-mercaptobutyl (diethoxymethylsilane),</li><li>3-mercapto- (2-methyl) propyl (dimethylmethoxysilane)</li><li>3-mercapto-2-methyl-propyl (dimethylethoxysilane)</li><li>3-mercapto-2-methyl-propyl (dimethyltetradecanoxysilane)</li><li>3-mercaptobutyl (dimethylmethoxysilane),</li><li>3-mercapto-2-methyl-propyl (dimethylethoxysilane)</li><li>3-mercapto- (2-methyl) propyl (dimethyl methoxysilane)</li><li>3-mercapto-2-methyl-propyl (dimethyltetradecanoxysilane)</li><li>3-mercaptobutyl (dimethylethoxysilane),</li><li>3-mercaptobutyl (tridodecanoxysilane),</li><li>3-mercaptobutyl (tritetradecanoxysilane),</li><li>3-mercaptobutyl (trihexadecanoxysilane),</li><li>3-mercaptobutyl (didodecanoxy) tetradecanoxysilane or</li><li>3-mercaptobutyl (dodecanoxy) tetradecanoxy (hexadecanoxy) silane.</li></ul>

In the process for the preparation of (mercaptoorganyl) alkoxysilanes, compounds of the general formula I or else mixtures of compounds of the general formula I can be formed.

As (halogenorganyl) alkoxysilanes, compounds of the general formula II<chemistry id="chem0003" num="0003"><img file="EP1538152B1_D0003.tif" /></chemistry>are used, where x, R, R 'and R "have the meaning given above and Hal is chlorine, bromine, fluorine or iodine.

Can preferably be used as (halogenorganyl) alkoxysilanes 3-chlorobutyl (triethoxysilane), 3-chlorobutyl (trimethoxysilane), 3-chlorobutyl (diethoxymethoxysilane), 3-chloropropyl (triethoxysilane), 3-chloropropyl (trimethoxysilane), 3-chloropropyl (diethoxymethoxysilane), 2-chloroethyl (triethoxysilane), 2-chloroethyl (trimethoxysilane), 2-chloroethyl (diethoxymethoxysilane), 1-chloromethyl (triethoxysilane), 1-chloromethyl (trimethoxysilane), 1-chloromethyldiethoxymethoxysilane), 3-chloropropyl (diethoxymethylsilane), 3-chloropropyl (dimethoxymethylsilane), 2-chloroethyl (diethoxymethylsilane), 2-chloroethyl (dimethoxymethylsilane), 1-chloromethyl (diethoxymethylsilane), 1-chloromethyl (dimethoxymethylsilane), 3-chloropropyl (ethoxydimethylsilane), 3-chloropropyl (methoxydimethylsilane), 2-chloroethyl (ethoxydimethylsilane), 2-chloroethyl (methoxydimethylsilane), 1-chloromethyl (ethoxydimethylsilane) or 1-Chloromethyl (methoxydimethylsilane) can be used.

The (halogenorganyl) alkoxysilane can be a (halogenorganyl) alkoxysilane of the formula II or a mixture of (halogenorganyl) alkoxysilanes of the formula II.

Compounds of the general formula III can be used as (haloganyl) halosilanes<chemistry id="chem0004" num="0004"><img file="EP1538152B1_D0004.tif" /></chemistry>are used, where x, Hal, R and R "have the meaning given above and R" "is independently of one another R or Hal.

Can preferably be used as (halogenorganyl) halosilanes 3-chlorobutyl (trichlorosilane), 3-chloropropyl (trichlorosilane), 2-chloroethyl (trichlorosilane), 1-chloromethyl (trichlorosilane), 3-chlorobutyl (dichloromethoxysilane), 3-chloropropyl (dichloromethoxysilane), 2-chloroethyl (dichloromethoxysilane), 1-chloromethyl (dichloromethoxysilane), 3-chlorobutyl (dichloroethoxysilane), 3-chloropropyl (dichloroethoxysilane), 2-chloroethyl (dichloroethoxysilane), 1-chloromethyl (dichloroethoxysilane), 3-chlorobutyl (chlorodiethoxysilane), 3-chloropropyl (chlorodiethoxysilane), 2-chloroethyl (chlorodiethoxysilane), 1-chloromethyl (chlorodiethoxysilane), 3-chlorobutyl (chlorodimethoxysilane), 3-chloropropyl (chlorodimethoxysilane), 2-chloroethyl (chlorodimethoxysilane), 1-chloromethyl (chlorodimethoxysilane), 3-chlorobutyl (dichloromethylsilane), 3-chloropropyl (dichloromethylsilane), 2-chloroethyl (dichloromethylsilane), 1-chloromethyl (dichloromethylsilane), 3-chlorobutyl (chloro-) (methyl-) methoxysilane), 3-chloropropyl (chloro -) (methyl) methoxysilane), 2-chloroethyl (chloro-) (methyl-) methoxysilane), 1-chloromethyl (chloro -) (methyl) methoxysilane), 3-chlorobutyl (chloro-) (methyl-) ethoxysilane), 3-chloropropyl (chloro -) (methyl) ethoxysilane), 2-chloroethyl (chloro -) (methyl) ethoxysilane), 1-chloromethyl (chloro-) (methyl-) ethoxysilane), 3-chlorobutyl (chlorodimethylsilane), 3-chloropropyl (chlorodimethylsilane), 2-chloroethyl (chlorodimethylsilane) or 1-Chloromethyl (chlorodimethylsilane) can be used.

The (haloorganyl) halosilane can be a (haloorganyl) halosilane of the general formula III or a mixture of (haloorganyl) halosilanes of the general formula III.

(Mercaptoorganyl) alkoxysilanes of the general formula I

<chemistry id="chem0005" num="0005"><img file="EP1538152B1_D0005.tif" /></chemistry>can by reaction of alkali metal bisulfide with (halogen organyl) alkoxysilanes of the general formula II<chemistry id="chem0006" num="0006"><img file="EP1538152B1_D0006.tif" /></chemistry> and (Halogenorganyl) halosilane of the general formula III<chemistry id="chem0007" num="0007"><img file="EP1538152B1_D0007.tif" /></chemistry>be prepared in an alcohol in a closed vessel with the exclusion of air and an increased pressure.

Through the choice of the (halogenorganyl) alkoxy-silanes and (halogenorganyl) halosilanes, the composition of mixtures of compounds of the general formula I can be influenced actively and in a targeted manner.

(Halogenorganyl) alkoxysilane and (halogenorganyl) halosilane can be in a molar ratio of 1: 0.00001 to 1: 0.8, preferably 1: 0.00001 to 1: 0.5, particularly preferably 1: 0.00001 to 1: 0 , 09, can be used.

The mixture of corresponding (haloorganyl) alkoxysilane and (haloorganyl) halosilane used for the process can, depending on the equipment used and the desired effects, for example selectivity of the reaction, duration of the reaction, reactor throughput, reaction of (haloorganyl) alkoxysilane and (haloorganyl) halosilane with one another, reactor material or process sequence, are prepared before the addition of the alkali metal sulfide.

The quality and type of the composition of the mixture of (halogenorganyl) alkoxysilane and (halogenorganyl) -halosilane can be assessed on the basis of the amount and type of hydrolyzable Si-Hal bonds contained in the mixture.

The amount of hydrolyzable Si-halide in the mixtures of halogenorganyl) alkoxysilane and (halogenorganyl) halosilane can be between 10 and 800000 mg / kg.

The amount of hydrolyzable Si halide is determined by the following procedure:

A maximum of 20 g of the sample are mixed in a 150 ml beaker with 80 ml of ethanol and 10 ml of acetic acid. The halide content is titrated potentiographically with silver nitrate solution (c (AgN03) = 0.01 mol / l).

The advantageous molar ratios of the mixtures of (halogeno organyl) alkoxysilanes and (halogeno organyl) halosilanes can depend, inter alia, on the number of Si-halogen functions of the (halogeno organyl) halosilanes chosen.

For example, a molar ratio of 1: 0.00001 to 1: 0.03 can preferably be used in the reaction of 3-chloropropyl (trimethoxysilane) or 3-chloropropyl (triethoxysilane) and 3-chloropropyl (trichlorosilane).

For example, a molar ratio of 1: 0.00001 to 1: 0.045 can preferably be used in the reaction of 3-chloropropyl (methyldimethoxysilane) or 3-chloropropyl (methyldiethoxysilane) and 3-chloropropyl (methyldichlorosilane).

For example, a molar ratio of 1: 0.00001 to 1: 0.09 can preferably be used in the reaction of 3-chloropropyl (dimethylmethoxysilane) or of 3-chloropropyl (dimethylethoxysilane) and 3-chloropropyl (dimethylchlorosilane).

The (halo organyl) alkoxysilane and (halo organyl) halosilane can be mixed with one another in any order, manner, temperature and length of time and only then can the alcohol and the alkali metal bisulfide be added together or in succession.

The (halo organyl) halosilane, alkali hydrogen sulfide and alcohol can be mixed with one another in any order, manner, temperature and length of time and only then can the (halo organyl) alkoxysilane be added.

The (halo organyl) alkoxysilane, alkali hydrogen sulfide and alcohol can be mixed with one another in any order, manner, temperature and length of time and only then can the (halo organyl) halosilane be added.

As the alkali metal hydrogen sulfide, lithium hydrogen sulfide (LiSH), sodium hydrogen sulfide (NaSH), potassium hydrogen sulfide (KSH) and cesium hydrogen sulfide (CsSH) can be used.

The molar amount of alkali metal hydrogen sulfide used can exceed the sum of the molar amounts of the (haloganyl) alkoxysilane and (haloganyl) halosilane used by 1% to 50%, preferably 5% to 25%, particularly preferably 5% to 15%.

Less than the stoichiometrically required amounts of alkali metal hydrogen sulfide can lead to incomplete conversion. As a result, the product can either be contaminated with starting material or complex distillation is necessary to separate the starting materials and products.

Primary, secondary or tertiary alcohols having 1 to 24, preferably 1 to 6, particularly preferably 1 to 4, carbon atoms can be used as the alcohol.

Methanol, ethanol, n-propanol, i-propanol, i-butanol, n-butanol, dodecanol, tetradecanol, hexadecanol or octadecanol can be used as primary, secondary or tertiary alcohols.

The amount of alcohol can be at least 100% by volume, preferably 250 to 1000% by volume, particularly preferably 500 to 1000% by volume, of the silane components used.

At the start of the reaction and / or during the reaction and / or at the end of the reaction, polar, protic, aprotic, basic or acidic additives can be added to the reaction mixture.

An elevated pressure can be understood to mean an overpressure of 0.1 to 10 bar, preferably 1 to 7 bar, above normal pressure.

The reaction can take place at temperatures between 0 and 180 ° C, preferably between 70 and 150 ° C, especially! preferably between 70 and 125 ° C.

The optimum reaction temperature in each case with regard to the yield of the target product and utilization of the reaction volume can vary depending on the structure of the (haloganyl) alkoxysilane used and the alcohol used as solvent.

For example, in reactions in methanol, a reaction temperature between 60 and 95 ° C can be advantageous in terms of reaction times, amount of by-products and pressure build-up.

For example, in reactions in ethanol a reaction temperature between 75 and 130 ° C can be advantageous in terms of reaction times, amount of by-products and pressure build-up.

The reaction can take place in a closed container under protective gas.

The reaction can take place in corrosion-resistant or corrosion-sensitive reaction vessels or autoclaves.

The corrosion-resistant reaction vessels or autoclaves can be made of glass, Teflon, enamelled or coated steel, Hastelloy or tantalum.

The amount of by-products can be less than 20 mol% by choosing the reaction conditions.

In addition to the desired mercaptoorganylsilane compounds, the corresponding monosulfanes or disulfanes and, as a function of the structure of the monomeric mercaptoorganylsilane compound, various combinations of dimeric or oligomeric siloxanes from products or products with starting materials can also be formed as by-products.

The process according to the invention has the advantage that it is possible to dispense with the use of highly toxic, gaseous substances such as hydrogen sulfide as the sulfur donor. Instead, alkali metal bisulfides, which are easily metered solids (e.g. sodium bisulfide), are used as sulfur donors.

Another advantage of the process according to the invention is that the selectivity can be increased simply by using a closed reaction vessel (autoclave or the like) and adding small amounts of (haloalkyl) halosilanes.

Another advantage of the method according to the invention compared to known methods is the high conversions with short batch times and at technically simple realizable temperatures.

Examples:

As the conversion in the reaction mixtures, the quotient of the<ul id="ul0010" list-style="dash" compact="compact"><li>Total area percentages from 3-mercaptopropyl (triethoxysilane), (EtO)₃Themselves₂)_3-S- (CH₂)₃-Si (OEt)₃ and (EtO)₃Themselves₂)₃-S₂- (CH₂)_3-Si (OEt)₃</li></ul>and the<ul id="ul0011" list-style="dash" compact="compact"><li>Total area percentages from 3-chloropropyl (triethoxysilane), 3-mercaptopropyl (triethoxysilane), (EtO)₃Themselves₂)₃-S- (CH₂)₃-Si (OEt)₃ and (EtO)₃Themselves₂)₃-S₂- (CH₂)₃-Si (OEt)₃</li></ul>Are defined.

As the turnover in the isolated raw product, the quotient of the<ul id="ul0012" list-style="dash" compact="compact"><li>Sum of percentages by weight of 3-mercaptopropyl (triethoxysilane) and (EtO)₃Themselves₂)₃-S- (CH₂)₃-Si (OEt)₃</li></ul>and the<ul id="ul0013" list-style="dash" compact="compact"><li>Sum of percentages by weight of 3-chloropropyl (triethoxysilane), 3-mercaptopropyl (triethoxysilane) and (EtO)₃Themselves₂)₃-S- (CH₂)₃-Si (OEt)₃</li></ul>Are defined.

The quotient is selected as the selectivity in the reaction mixtures<ul id="ul0014" list-style="dash" compact="compact"><li>the area percent of 3-mercaptopropyl (triethoxysilane)</li></ul>and the<ul id="ul0015" list-style="dash" compact="compact"><li>Total area percentages from 3-mercaptopropyl (triethoxysilane), (EtO)₃Themselves₂)₃-S- (CH2)₃-Si (OEt)₃ and (EtO)₃Themselves₂)₃-S₂- (CH₂)₃-Si (OEt)₃</li></ul>Are defined.

The quotient is selected as selectivity in the isolated crude product<ul id="ul0016" list-style="dash" compact="compact"><li>the weight percent of 3-mercaptopropyl (triethoxysilane)</li></ul>and the<ul id="ul0017" list-style="dash" compact="compact"><li>Sum of percentages by weight of 3-mercaptopropyl (triethoxysilane) and (EtO)₃Themselves₂)_3-S- (CH₂)₃-Si (OEt)</li></ul>Are defined.

Dried NaSH is available as a commercial product, for example from STREM / ABCR.

GC analytics

The GC analysis of the reaction mixtures is carried out on a HP 6890 (WLD) gas chromatograph with a 30 m long DB5 column with a thickness of 0.53 mm and a film thickness of 1.5 µm. A thermal conductivity detector is used as the detector. The temperature program used included the following processes:<ul id="ul0018" list-style="dash" compact="compact"><li>Start temperature 100 ° C</li><li>Initial time 1 min.</li><li>20 ° C / min to 280 ° C</li><li>Hold 280 ° C for 10 minutes</li></ul>

The retention times for the following components are:<ul id="ul0019" list-style="none" compact="compact"><li>at 3.3 min = Cl- (CH₂)₃-Si (OEt)₃</li><li>at 5.7 min Si263 = HS- (CH₂)₃-Si (OEt)₃</li><li>at 9.0-10.5 min different siloxane dimers from educt and product silane</li><li>at 11.0 min = (EtO)₃Themselves₂)₃-S- (CH₂) 3-Si (OEt)₃</li><li>at 12.4 min = (EtO)₃Themselves₂)₃-S₂- (CH₂)₃-Si (OEt)₃</li></ul>

Comparative Example 1:

Example 1 from GB 1,102,251 gives an isolated yield of 42%.

Comparative Example 2:

Comparative example 3 from US Pat. No. 5,840,952 gives 81% with a yield determined by GC.

Comparative Example 3:

Comparative example 5 from US Pat. No. 5,840,952 gives 40.3% with a yield determined by GC.

Comparative Example 4:

50 g of 3-chloropropyl (triethoxysilane) and 125 ml of dry ethanol are mixed at room temperature in a stainless steel autoclave with a glass insert. 11.7 g of dried NaSH are added to the solution and the autoclave is then sealed airtight. The reaction mixture is heated in an autoclave at 100 ° C. for 120 min and then cooled to room temperature. The GC measurement of the reaction mixture gives the following composition in area percent (F1.%):<tables id="tabl0001" num="0001"><table frame="all"><tgroup cols="2" colsep="1" rowsep="1"><colspec colnum="1" colname="col1" colwidth="128mm" colsep="1" /><colspec colnum="2" colname="col2" colwidth="19mm" colsep="1" /><tbody><row><entry namest="col1" nameend="col1" align="left" valign="top">3-chloropropyl (triethoxysilane)</entry><entry namest="col2" nameend="col2" valign="top" align="char" char="." charoff="52">1.5 bt%,</entry></row><row><entry namest="col1" nameend="col1" align="left" valign="top">3-mercaptopropyl (triethoxysilane)</entry><entry namest="col2" nameend="col2" valign="top" align="char" char="." charoff="52">18.4 bt%,</entry></row><row><entry namest="col1" nameend="col1" align="left" valign="top">dimeric siloxanes from 3-chloropropyl (triethoxysilane) and 3-mercaptopropyl (triethoxysilane)</entry><entry namest="col2" nameend="col2" valign="top" align="char" char="." charoff="52">0.3 bt%,</entry></row><row><entry namest="col1" nameend="col1" align="left" valign="top">Bis (triethoxysilypropyl) monosulfane</entry><entry namest="col2" nameend="col2" valign="top" align="char" char="." charoff="52">3.2 bt%</entry></row><row><entry namest="col1" nameend="col1" align="left" valign="top">Bis (triethoxysilypropyl) disulfane</entry><entry namest="col2" nameend="col2" valign="top" align="char" char="." charoff="52">0.3 bt%</entry></row></tbody></tgroup></table></tables>The conversion is 93.7% and the selectivity 82.9%.

Comparative Example 5:

50 g of 3-chloropropyl (triethoxysilane) and 125 ml of dry ethanol are mixed at room temperature in a stainless steel autoclave with a glass insert. 11.7 g of dried NaSH are added to the solution and the autoclave is then sealed airtight. The reaction mixture is heated in an autoclave to 90 ° C. for 240 min and then cooled to room temperature. The GC measurement of the reaction mixture gives the following composition in area percent (area%):<tables id="tabl0002" num="0002"><table frame="all"><tgroup cols="2" colsep="1" rowsep="1"><colspec colnum="1" colname="col1" colwidth="128mm" colsep="1" /><colspec colnum="2" colname="col2" colwidth="19mm" colsep="1" /><tbody><row><entry namest="col1" nameend="col1" align="left" valign="top">3-chloropropyl (triethoxysilane)</entry><entry namest="col2" nameend="col2" valign="top" align="char" char="." charoff="52">1.5 bt%,</entry></row><row><entry namest="col1" nameend="col1" align="left" valign="top">3-mercaptopropyl (triethoxysilane)</entry><entry namest="col2" nameend="col2" valign="top" align="char" char="." charoff="52">18.8 bt%,</entry></row><row><entry namest="col1" nameend="col1" align="left" valign="top">dimeric siloxanes from 3-chloropropyl (triethoxysilane) and 3-mercaptopropyl (triethoxysilane)</entry><entry namest="col2" nameend="col2" valign="top" align="char" char="." charoff="52">0.4 bt%,</entry></row><row><entry namest="col1" nameend="col1" align="left" valign="top">Bis (triethoxysilypropyl) monosulfane</entry><entry namest="col2" nameend="col2" valign="top" align="char" char="." charoff="52">2.7 bt%</entry></row><row><entry namest="col1" nameend="col1" align="left" valign="top">Bis (triethoxysilypropyl) disulfane</entry><entry namest="col2" nameend="col2" valign="top" align="char" char="." charoff="52">0.5 bt%</entry></row></tbody></tgroup></table></tables>The conversion is 93.7% and the selectivity 84%.

Example 1:

50 g of 3-chloropropyl (triethoxysilane), 0.5 g of 3-chloropropyl (trichlorosilane) and 125 ml of dry ethanol are mixed at room temperature in a stainless steel autoclave with a glass insert. 13.5 g of dried NaSH are added to the solution and the autoclave is then sealed airtight. The reaction mixture is heated in an autoclave to 90 ° C. for 240 min and then cooled to room temperature. The GC measurement of the reaction mixture gives the following composition in area percent (area%):<tables id="tabl0003" num="0003"><table frame="all"><tgroup cols="2" colsep="1" rowsep="1"><colspec colnum="1" colname="col1" colwidth="128mm" colsep="1" /><colspec colnum="2" colname="col2" colwidth="19mm" colsep="1" /><tbody><row><entry namest="col1" nameend="col1" align="left" valign="top">3-chloropropyl (triethoxysilane)</entry><entry namest="col2" nameend="col2" valign="top" align="char" char="." charoff="52">2.5 bt%,</entry></row><row><entry namest="col1" nameend="col1" align="left" valign="top">3-mercaptopropyl (triethoxysilane)</entry><entry namest="col2" nameend="col2" valign="top" align="char" char="." charoff="52">37.0 bt%,</entry></row><row><entry namest="col1" nameend="col1" align="left" valign="top">dimeric siloxanes from 3-chloropropyl (triethoxysilane) and 3-mercaptopropyl (triethoxysilane)</entry><entry namest="col2" nameend="col2" valign="top" align="char" char="." charoff="52">2.2 bt%,</entry></row><row><entry namest="col1" nameend="col1" align="left" valign="top">Bis (triethoxysilypropyl) monosulfane</entry><entry namest="col2" nameend="col2" valign="top" align="char" char="." charoff="52">1.9 bt%</entry></row><row><entry namest="col1" nameend="col1" align="left" valign="top">Bis (triethoxysilypropyl) disulfane</entry><entry namest="col2" nameend="col2" valign="top" align="char" char="." charoff="52">0.9 bt%</entry></row></tbody></tgroup></table></tables>The conversion is 94.3% and the selectivity 88%.

Example 2:

50 g of 3-chloropropyl (triethoxysilane), 1.0 g of 3-chloropropyl (trichlorosilane) and 125 ml of dry ethanol are mixed at room temperature in a stainless steel autoclave with a glass insert. 13.5 g of dried NaSH are added to the solution and the autoclave is then sealed airtight. The reaction mixture is heated in an autoclave at 100 ° C. for 120 min and then cooled to room temperature. The GC measurement of the reaction mixture gives the following composition in area percent (area%):<tables id="tabl0004" num="0004"><table frame="all"><tgroup cols="2" colsep="1" rowsep="1"><colspec colnum="1" colname="col1" colwidth="128mm" colsep="1" /><colspec colnum="2" colname="col2" colwidth="19mm" colsep="1" /><tbody><row><entry namest="col1" nameend="col1" align="left" valign="top">3-chloropropyl (triethoxysilane)</entry><entry namest="col2" nameend="col2" valign="top" align="char" char="." charoff="52">0.9 bt%,</entry></row><row><entry namest="col1" nameend="col1" align="left" valign="top">3-mercaptopropyl (triethoxysilane)</entry><entry namest="col2" nameend="col2" valign="top" align="char" char="." charoff="52">19.6 bt%,</entry></row><row><entry namest="col1" nameend="col1" align="left" valign="top">dimeric siloxanes from 3-chloropropyl (triethoxysilane) and 3-mercaptopropyl (triethoxysilane)</entry><entry namest="col2" nameend="col2" valign="top" align="char" char="." charoff="52">0.3 bt%,</entry></row><row><entry namest="col1" nameend="col1" align="left" valign="top">Bis (triethoxysilypropyl) monosulfane</entry><entry namest="col2" nameend="col2" valign="top" align="char" char="." charoff="52">1.2 bt%</entry></row><row><entry namest="col1" nameend="col1" align="left" valign="top">Bis (triethoxysilypropyl) disulfane</entry><entry namest="col2" nameend="col2" valign="top" align="char" char="." charoff="52">0.6 bt%</entry></row></tbody></tgroup></table></tables>The conversion is 96% and the selectivity 90%.

Example 3:

28.6 g of dried NaSH and 600 ml of dry ethanol are placed in an autoclave with a double glass jacket and Hastelloy C22 lid + fittings (Buechi AG) at room temperature and stirred at 50 ° C. for 15 min. 5 g of 3-chloropropyl (trichlorosilane) are added to the suspension with a pressure burette and the suspension is stirred for a further 10 min. 100 g of 3-chloropropyl (triethoxysilane) and 200 ml of ethanol are added to the suspension via the burette. The mixture is heated to 93-96 ° C. with stirring and the temperature is kept for 120 min. The mixture is then cooled to room temperature and a sample is taken. The GC analysis of the reaction mixture shows the following composition in area percent:<tables id="tabl0005" num="0005"><table frame="all"><tgroup cols="2" colsep="1" rowsep="1"><colspec colnum="1" colname="col1" colwidth="58mm" colsep="1" /><colspec colnum="2" colname="col2" colwidth="14mm" colsep="1" /><tbody><row><entry namest="col1" nameend="col1" align="left" valign="top">3-chloropropyl (triethoxysilane)</entry><entry namest="col2" nameend="col2" valign="top" align="char" char="." charoff="67">0,728</entry></row><row><entry namest="col1" nameend="col1" align="left" valign="top">3-mercaptopropyl (triethoxysilane)</entry><entry namest="col2" nameend="col2" valign="top" align="char" char="." charoff="67">6,099</entry></row><row><entry namest="col1" nameend="col1" align="left" valign="top">(EtO)₃Themselves₂)₃-S- (CH₂)₃-Si (OEt)₃</entry><entry namest="col2" nameend="col2" valign="top" align="char" char="." charoff="67">0, 078</entry></row><row><entry namest="col1" nameend="col1" align="left" valign="top">(EtO)₃Themselves₂)₃-S₂- (CH₂)₃-Si (OEC)₃</entry><entry namest="col2" nameend="col2" valign="top" align="char" char="." charoff="67">0,061</entry></row></tbody></tgroup></table></tables>Based on the above values, the conversion is 90% and the selectivity of the reaction is 98%.

The suspension obtained is filtered. The separated solid is washed with 600 ml of n-pentane. The solution obtained is freed from the volatile constituents at 20-600 mbar and 80-110 ° C. on a rotary evaporator. The suspension obtained is mixed well with 200 ml of pentane and stored at 4-8 ° C. for 13-14 h. The precipitated solid is separated off by filtration and washed with pentane. The pentane is removed from the clear solution obtained using a rotary evaporator at 20-600 mbar and 80-110 ° C. 99.6 g of a colorless liquid are obtained.

Analysis with GC (dodecane as internal standard) shows the following composition of the product obtained in percent by weight:<tables id="tabl0006" num="0006"><table frame="all"><tgroup cols="2" colsep="1" rowsep="1"><colspec colnum="1" colname="col1" colwidth="62mm" colsep="1" /><colspec colnum="2" colname="col2" colwidth="12mm" colsep="1" /><tbody><row><entry namest="col1" nameend="col1" align="left" valign="top">3-chloropropyl (triethoxysilane) (GC)</entry><entry namest="col2" nameend="col2" align="center" valign="top">9</entry></row><row><entry namest="col1" nameend="col1" align="left" valign="top">3-mercaptopropyl (triethoxysilane) (GC)</entry><entry namest="col2" nameend="col2" align="center" valign="top">86,5</entry></row><row><entry namest="col1" nameend="col1" align="left" valign="top">(EtO)₃Themselves₂)₃-S- (CH₂)₃-Si (OEt)₃ (GC)</entry><entry namest="col2" nameend="col2" align="center" valign="top">3,3</entry></row></tbody></tgroup></table></tables>Based on the above values, the conversion is 91% and the selectivity of the reaction is 96%.

Example 4:

37.5 g of dried NaSH and 600 ml of dry ethanol are placed in an autoclave with a double glass jacket and Hastelloy C22 lid + fittings (Buechi AG) at room temperature. The suspension is heated and stirred at 50 ° C for 20 min. A mixture of 100 g of 3-chloropropyl (dimethylethoxysilane) and 5 g of 3-chloropropyl (dimethylchlorosilane) is added to the suspension with a pressure burette. A further 200 ml of ethanol are added to the mixture and heated to 93-96 ° C. with stirring. The temperature is held for 180 min. The mixture is then cooled to room temperature. A sample is taken and analyzed by gas chromatography. The GC analysis of the reaction mixture shows the following composition in area percent:<tables id="tabl0007" num="0007"><table frame="all"><tgroup cols="2" colsep="1" rowsep="1"><colspec colnum="1" colname="col1" colwidth="72mm" colsep="1" /><colspec colnum="2" colname="col2" colwidth="13mm" colsep="1" /><tbody><row><entry namest="col1" nameend="col1" align="left" valign="top">3-chloropropyl (dimethylethoxysilane)</entry><entry namest="col2" nameend="col2" valign="top" align="char" char="." charoff="65">0,091</entry></row><row><entry namest="col1" nameend="col1" align="left" valign="top">3-mercaptopropyl (dimethylethoxysilane)</entry><entry namest="col2" nameend="col2" valign="top" align="char" char="." charoff="65">4,621</entry></row><row><entry namest="col1" nameend="col1" align="left" valign="top">(EtO) (CH₃)₂Themselves₂)₃-S- (CH₂)₃-Themselves₃)₂(OEt)</entry><entry namest="col2" nameend="col2" valign="top" align="char" char="." charoff="65">0,074</entry></row><row><entry namest="col1" nameend="col1" align="left" valign="top">(EtO) (CH₃)₂Themselves₂)₃-S₂- (CH₂)₃-Themselves₃)₂(OEt)</entry><entry namest="col2" nameend="col2" valign="top" align="char" char="." charoff="65">0,155</entry></row></tbody></tgroup></table></tables>Based on the above values, the conversion is 98% and the selectivity of the reaction is 95%.

Example 5:

36.2 g of dried NaSH and 800 ml of dry ethanol are placed in an autoclave with a double glass jacket and Hastelloy C22 lid + fittings (Buechi AG) at room temperature, heated and stirred at 50 ° C. for 15 min. A mixture of 100 g of 3-chloropropyl (triethoxysilane) and 20 g of a silane mixture of 3-chloropropyl (diethoxy (chloro) silane), 3-chloropropyl (ethoxy (dichloro) silane), 3-chloropropyl (trichlorosilane) and 3- Chloropropyl (triethoxysilane) was added to the suspension with a pressure burette. The 20 g are taken from a silane mixture which is obtained by reaction from 694.2 g of 3-chloropropyl (triethoxysilane) and 350.8 g of 3-chloropropyl (trichlorosilane). 200 ml of ethanol are metered in via the burette and heated to 102-104 ° C. with stirring. The temperature is held for 180 min. The mixture is then cooled to approximately 55 ° C. and 2.6 g of formic acid in 100 ml of ethanol are metered in using a pressure burette. After 15 minutes, a sample is taken and analyzed by gas chromatography. The GC analysis of the reaction mixture shows the following composition in area percent:<tables id="tabl0008" num="0008"><table frame="all"><tgroup cols="2" colsep="1" rowsep="1"><colspec colnum="1" colname="col1" colwidth="57mm" colsep="1" /><colspec colnum="2" colname="col2" colwidth="13mm" colsep="1" /><tbody><row><entry namest="col1" nameend="col1" align="left" valign="top">3-chloropropyl (triethoxysilane)</entry><entry namest="col2" nameend="col2" valign="top" align="char" char="." charoff="65">0,034</entry></row><row><entry namest="col1" nameend="col1" align="left" valign="top">3-mercaptopropyl (triethoxysilane)</entry><entry namest="col2" nameend="col2" valign="top" align="char" char="." charoff="65">5,494</entry></row><row><entry namest="col1" nameend="col1" align="left" valign="top">(EtO)₃Themselves₂)₃-S- (CH₂)₃-Si (OEt)₃</entry><entry namest="col2" nameend="col2" valign="top" align="char" char="." charoff="65">0,060</entry></row><row><entry namest="col1" nameend="col1" align="left" valign="top">(EtO)₃Themselves₂)₃-S₂- (CH₂)₃-Si (OEt)₃</entry><entry namest="col2" nameend="col2" valign="top" align="char" char="." charoff="65">0,028</entry></row></tbody></tgroup></table></tables>Based on the above values, the conversion is&gt; 99% and the selectivity of the reaction is 98%.

The suspension obtained is filtered. The separated solid is washed with 400 ml of n-pentane. The solution obtained is freed from the volatile constituents at 20-600 mbar and 60-80 ° C. on a rotary evaporator. The suspension obtained is mixed with 200 ml of pentane and stored at 4-8 ° C. for 10 h. The precipitated solid is separated off by filtration and washed with 150 ml of pentane. The pentane is removed from the solution obtained using a rotary evaporator at 20-600 mbar and 60-80 ° C. 111.2 g of a colorless liquid are obtained.

Analysis with GC (dodecane as internal standard) shows the following composition of the product obtained in percent by weight:<tables id="tabl0009" num="0009"><table frame="all"><tgroup cols="2" colsep="1" rowsep="1"><colspec colnum="1" colname="col1" colwidth="62mm" colsep="1" /><colspec colnum="2" colname="col2" colwidth="12mm" colsep="1" /><tbody><row><entry namest="col1" nameend="col1" align="left" valign="top">3-chloropropyl (triethoxysilane) (GC)</entry><entry namest="col2" nameend="col2" valign="top" align="char" char="." charoff="59">0,6</entry></row><row><entry namest="col1" nameend="col1" align="left" valign="top">3-mercaptopropyl (triethoxysilane) (GC)</entry><entry namest="col2" nameend="col2" valign="top" align="char" char="." charoff="59">96,2</entry></row><row><entry namest="col1" nameend="col1" align="left" valign="top">(EtO)₃Themselves₂)₃-S- (CH₂)₃-Si (OEt)₃ (GC)</entry><entry namest="col2" nameend="col2" valign="top" align="char" char="." charoff="59">2,1</entry></row></tbody></tgroup></table></tables>Based on the above values, the conversion is&gt; 99% and the selectivity of the reaction is 98%.

Example 6:

33.6 g of dried NaSH and 800 ml of dry ethanol are placed in an autoclave with a double glass jacket and Hastelloy C22 lid + fittings (Buechi AG) at room temperature and stirred at 50 ° C. for 15 min. A mixture of 97 g of 3-chloropropyl (triethoxysilane) and 20 g of a silane mixture of 3-chloropropyl (diethoxy (chloro) silane), 3-chloropropyl (ethoxy (dichloro) silane), 3-chloropropyl (trichlorosilane) and 3- Chloropropyl (triethoxysilane) was added to the suspension with a burette operated with compressed air. The 20 g are taken from a silane mixture which is obtained by reaction from 694.2 g of 3-chloropropyl (triethoxysilane) and 350.8 g of 3-chloropropyl (trichlorosilane). A further 200 ml of ethanol are added to the suspension via the burette. The mixture is heated to 109-110 ° C with stirring and the temperature is maintained for 240 min. The mixture is then cooled to room temperature. A sample is taken and analyzed by gas chromatography. The GC analysis of the reaction mixture shows the following composition in area percent:<tables id="tabl0010" num="0010"><table frame="all"><tgroup cols="2" colsep="1" rowsep="1"><colspec colnum="1" colname="col1" colwidth="57mm" colsep="1" /><colspec colnum="2" colname="col2" colwidth="13mm" colsep="1" /><tbody><row><entry namest="col1" nameend="col1" align="left" valign="top">3-chloropropyl (triethoxysilane)</entry><entry namest="col2" nameend="col2" valign="top" align="char" char="." charoff="65">0,148</entry></row><row><entry namest="col1" nameend="col1" align="left" valign="top">3-mercaptopropyl (triethoxysilane)</entry><entry namest="col2" nameend="col2" valign="top" align="char" char="." charoff="65">6,822</entry></row><row><entry namest="col1" nameend="col1" align="left" valign="top">(EtO)₃Themselves₂)₃-S- (CH₂)₃-Si (OEt)₃</entry><entry namest="col2" nameend="col2" valign="top" align="char" char="." charoff="65">0,085</entry></row><row><entry namest="col1" nameend="col1" align="left" valign="top">(EtO)₃Themselves₂)₃-S₂- (CH₂)₃-Si (OEt)₃</entry><entry namest="col2" nameend="col2" valign="top" align="char" char="." charoff="65">0,084</entry></row></tbody></tgroup></table></tables>Based on the above values, the conversion is 98% and the selectivity of the reaction is 98%.

The suspension obtained is filtered. The separated solid is washed with 400 ml of n-pentane. The solution obtained is freed from the volatile constituents at 20-600 mbar and 80-110 ° C. on a rotary evaporator. The suspension obtained is mixed well with 200 ml of pentane and stored at 4-8 ° C. for 3-4 h. The precipitated solid is separated off by filtration and washed with pentane. The pentane is removed from the clear solution obtained using a rotary evaporator at 20-600 mbar and 80-110 ° C. 110.3 g of a colorless liquid are obtained.

Analysis with GC (dodecane as internal standard) shows the following composition of the product obtained in percent by weight:<tables id="tabl0011" num="0011"><table frame="all"><tgroup cols="2" colsep="1" rowsep="1"><colspec colnum="1" colname="col1" colwidth="62mm" colsep="1" /><colspec colnum="2" colname="col2" colwidth="12mm" colsep="1" /><tbody><row><entry namest="col1" nameend="col1" align="left" valign="top">3-chloropropyl (triethoxysilane) (GC)</entry><entry namest="col2" nameend="col2" valign="top" align="char" char="." charoff="59">1,7</entry></row><row><entry namest="col1" nameend="col1" align="left" valign="top">3-mercaptopropyl (triethoxysilane) (GC)</entry><entry namest="col2" nameend="col2" valign="top" align="char" char="." charoff="59">94,8</entry></row><row><entry namest="col1" nameend="col1" align="left" valign="top">(EtO)₃Themselves₂)₃-S- (CH₂)₃-Si (OEt)₃ (GC)</entry><entry namest="col2" nameend="col2" valign="top" align="char" char="." charoff="59">2,4</entry></row></tbody></tgroup></table></tables>Based on the above values, the conversion is 98% and the selectivity of the reaction is 97%.

Example 7:

33.6 g of dried NaSH and 800 ml of dry ethanol are placed in an autoclave with a double glass jacket and Hastelloy C22 lid + fittings (Buechi AG) at room temperature and stirred at 50 ° C. for 15 min. A mixture of 100 g of 3-chloropropyl (triethoxysilane) and 20 g of a silane mixture of 3-chloropropyl (diethoxy (chloro) silane), 3-chloropropyl (ethoxy (dichloro) silane), 3-chloropropyl (trichlorosilane) and 3- Chloropropyl (triethoxysilane) was added to the suspension with a burette operated with compressed air. The 20 g are taken from a silane mixture which is obtained by reaction from 694.2 g of 3-chloropropyl (triethoxysilane) and 350.8 g of 3-chloropropyl (trichlorosilane). A further 200 ml of ethanol are added to the suspension via the burette, heated to 108-111 ° C. and the temperature maintained for 240 min. The mixture is then cooled to room temperature and a sample is taken. The GC analysis of the reaction mixture shows the following composition in area percent:<tables id="tabl0012" num="0012"><table frame="all"><tgroup cols="2" colsep="1" rowsep="1"><colspec colnum="1" colname="col1" colwidth="57mm" colsep="1" /><colspec colnum="2" colname="col2" colwidth="13mm" colsep="1" /><tbody><row><entry namest="col1" nameend="col1" align="left" valign="top">3-chloropropyl (triethoxysilane)</entry><entry namest="col2" nameend="col2" valign="top" align="char" char="." charoff="65">0,310</entry></row><row><entry namest="col1" nameend="col1" align="left" valign="top">3-mercaptopropyl (triethoxysilane)</entry><entry namest="col2" nameend="col2" valign="top" align="char" char="." charoff="65">5,151</entry></row><row><entry namest="col1" nameend="col1" align="left" valign="top">(EtO)₃Themselves₂)₃-S- (CH₂)₃-Si (OEt)₃</entry><entry namest="col2" nameend="col2" valign="top" align="char" char="." charoff="65">0,097</entry></row><row><entry namest="col1" nameend="col1" align="left" valign="top">(EtO)₃Themselves₂)₃-S₂- (CH₂)₃-Si (OEt)₃</entry><entry namest="col2" nameend="col2" valign="top" align="char" char="." charoff="65">0,254</entry></row></tbody></tgroup></table></tables>Based on the above values, the conversion is 95% and the selectivity of the reaction is 94%.

The suspension obtained is filtered. The separated solid is washed with 400 ml of n-pentane. The solution obtained is freed from the volatile constituents at 20-600 mbar and 80-110 ° C. on a rotary evaporator. The suspension obtained is mixed well with 200 ml of pentane and stored at 4-8 ° C. for 3-4 h. The precipitated solid is separated off by filtration and washed with pentane. The pentane is removed from the solution obtained using a rotary evaporator at 20-600 mbar and 80-110 ° C. 113.2 g of a colorless liquid are obtained.

The analysis with GC (dodecane as internal standard shows the following composition of the product obtained in percent by weight:<tables id="tabl0013" num="0013"><table frame="all"><tgroup cols="2" colsep="1" rowsep="1"><colspec colnum="1" colname="col1" colwidth="62mm" colsep="1" /><colspec colnum="2" colname="col2" colwidth="12mm" colsep="1" /><tbody><row><entry namest="col1" nameend="col1" align="left" valign="top">3-chloropropyl (triethoxysilane) (GC)</entry><entry namest="col2" nameend="col2" align="center" valign="top">5,1</entry></row><row><entry namest="col1" nameend="col1" align="left" valign="top">3-mercaptopropyl (triethoxysilane) (GC)</entry><entry namest="col2" nameend="col2" align="center" valign="top">92,2</entry></row><row><entry namest="col1" nameend="col1" align="left" valign="top">(EtO)₃Themselves₂)₃-S- (CH₂)₃-Si (OEt)₃ (GC)</entry><entry namest="col2" nameend="col2" align="center" valign="top">2</entry></row></tbody></tgroup></table></tables>Based on the above values, the conversion is 95% and the selectivity of the reaction is 98%.

Example 8:

18.1 g of dried NaSH and 400 ml of dry ethanol are placed in an autoclave with a double glass jacket and Hastelloy C22 lid + fittings (Buechi AG) at room temperature, heated and stirred at 50 ° C. for 15 min. A mixture of 50 g of 3-chloropropyl (triethoxysilane) and 10 g of a silane mixture of 3-chloropropyl (diethoxy (chloro) silane), 3-chloropropyl (ethoxy (dichloro) silane), 3-chloropropyl (trichlorosilane) and 3- Chloropropyl (triethoxysilane) was added to the suspension with a pressure burette. The 10 g are taken from a silane mixture which is obtained by reaction from 694.2 g of 3-chloropropyl (triethoxysilane) and 350.8 g of 3-chloropropyl (trichlorosilane). A further 100 ml of ethanol are added to the suspension via the burette. The mixture is heated to 105-110 ° C. with stirring and the temperature is kept for 180 min. The mixture is then cooled to 50 ° C. and 1.3 g of formic acid in 50 ml of ethanol are metered in using the pressure burette. The suspension is stirred for a further 15 min and a sample is taken. The GC analysis of the reaction mixture shows the following composition in area percent:<tables id="tabl0014" num="0014"><table frame="all"><tgroup cols="2" colsep="1" rowsep="1"><colspec colnum="1" colname="col1" colwidth="55mm" colsep="1" /><colspec colnum="2" colname="col2" colwidth="13mm" colsep="1" /><tbody><row><entry namest="col1" nameend="col1" align="left" valign="top">3-chloropropyl (triethoxysilane)</entry><entry namest="col2" nameend="col2" valign="top" align="char" char="." charoff="65">0,043</entry></row><row><entry namest="col1" nameend="col1" align="left" valign="top">3-mercaptopropyl (triethoxysilane)</entry><entry namest="col2" nameend="col2" valign="top" align="char" char="." charoff="65">4,908</entry></row><row><entry namest="col1" nameend="col1" align="left" valign="top">(EtO)₃Themselves₂)₃-S- (CH₂)₃-Si (OEt)₃</entry><entry namest="col2" nameend="col2" valign="top" align="char" char="." charoff="65">0,112</entry></row><row><entry namest="col1" nameend="col1" align="left" valign="top">(EtO)₃Themselves₂) -S₂- (CH₂)₃-Si (OEt)₃</entry><entry namest="col2" nameend="col2" valign="top" align="char" char="." charoff="65">0,033</entry></row></tbody></tgroup></table></tables>Based on the above values, the conversion is&gt; 99% and the selectivity of the reaction is 97%.

The suspension obtained is filtered and the separated solid is washed with 400 ml of n-pentane.

The solution obtained is freed from the volatile constituents at 20-600 mbar and 60-80 ° C. on a rotary evaporator. The suspension obtained is mixed with 200 ml of pentane and stored at 4-8 ° C. for 10 h. The precipitated solid is separated off by filtration and washed with 150 ml of pentane. The pentane is removed from the solution obtained using a rotary evaporator at 20-600 mbar and 60-80 ° C. 55.6 g of a colorless liquid are obtained.

Analysis with GC (dodecane as internal standard) shows the following composition of the product obtained in percent by weight:<tables id="tabl0015" num="0015"><table frame="all"><tgroup cols="2" colsep="1" rowsep="1"><colspec colnum="1" colname="col1" colwidth="62mm" colsep="1" /><colspec colnum="2" colname="col2" colwidth="12mm" colsep="1" /><tbody><row><entry namest="col1" nameend="col1" align="left" valign="top">3-chloropropyl (triethoxysilane) (GC)</entry><entry namest="col2" nameend="col2" valign="top" align="char" char="." charoff="59">0,7</entry></row><row><entry namest="col1" nameend="col1" align="left" valign="top">3-mercaptopropyl (triethoxysilane) (GC)</entry><entry namest="col2" nameend="col2" valign="top" align="char" char="." charoff="59">92,5</entry></row><row><entry namest="col1" nameend="col1" align="left" valign="top">(EtO)₃Themselves₂)₃-S- (CH₂)₃-Si (OEt)₃ (GC)</entry><entry namest="col2" nameend="col2" valign="top" align="char" char="." charoff="59">3,7</entry></row></tbody></tgroup></table></tables>Based on the above values, the conversion is&gt; 99% and the selectivity of the reaction is 96%.

Example 9:

36.2 g of dried NaSH and 800 ml of dry ethanol are placed in an autoclave with a double glass jacket and Hastelloy C22 cover + fittings (Buechi AG) at room temperature and stirred at 30 ° C. for 15 min. A mixture of 100 g of 3-chloropropyl (triethoxysilane) and 20 g of a silane mixture of 3-chloropropyl (diethoxy (chloro) silane), 3-chloropropyl (ethoxy (dichloro) silane), 3-chloropropyl (trichlorosilane) and 3- Chloropropyl (triethoxysilane) was added to the suspension with a pressure burette. The 20 g are taken from a silane mixture which is obtained by reaction from 694.2 g of 3-chloropropyl (triethoxysilane) and 350.8 g of 3-chloropropyl (trichlorosilane). A further 200 ml of ethanol are added to the suspension via the burette, heated to 102-104 ° C. with stirring and the temperature is maintained for 180 min. The mixture is then cooled to approximately 57 ° C. and 2.6 g of formic acid in 100 ml of ethanol are metered in using the pressure burette. The mixture is stirred for a further 15 min and a sample is taken. The GC analysis of the reaction mixture shows the following composition in area percent:<tables id="tabl0016" num="0016"><table frame="all"><tgroup cols="2" colsep="1" rowsep="1"><colspec colnum="1" colname="col1" colwidth="57mm" colsep="1" /><colspec colnum="2" colname="col2" colwidth="13mm" colsep="1" /><tbody><row><entry namest="col1" nameend="col1" align="left" valign="top">3-chloropropyl (triethoxysilane)</entry><entry namest="col2" nameend="col2" valign="top" align="char" char="." charoff="65">0,036</entry></row><row><entry namest="col1" nameend="col1" align="left" valign="top">3-mercaptopropyl (triethoxysilane)</entry><entry namest="col2" nameend="col2" valign="top" align="char" char="." charoff="65">4,754</entry></row><row><entry namest="col1" nameend="col1" align="left" valign="top">(EtO)₃Themselves₂)₃-S- (CH₂)₃-Si (OEt)₃</entry><entry namest="col2" nameend="col2" valign="top" align="char" char="." charoff="65">0,041</entry></row><row><entry namest="col1" nameend="col1" align="left" valign="top">(EtO)₃Themselves₂)₃-S₂- (CH₂)₃-Si (OEt)₃</entry><entry namest="col2" nameend="col2" valign="top" align="char" char="." charoff="65">0,026</entry></row></tbody></tgroup></table></tables>Based on the above values, the conversion is&gt; 99% and the selectivity of the reaction is 98%.

The suspension obtained is filtered. The separated solid is washed with 400 ml of n-pentane. The solution obtained is freed from the volatile constituents at 20-600 mbar and 60-80 ° C. on a rotary evaporator. The suspension obtained is mixed well with 200 ml of pentane and stored at 4-8 ° C. for 10 h. The precipitated solid is separated off by filtration and washed with 150 ml of pentane. The pentane is removed from the solution obtained using a rotary evaporator at 20-600 mbar and 60-80 ° C. 111.6 g of a colorless liquid are obtained.

Analysis with GC (dodecane as internal standard) shows the following composition of the product obtained in percent by weight:<tables id="tabl0017" num="0017"><table frame="all"><tgroup cols="2" colsep="1" rowsep="1"><colspec colnum="1" colname="col1" colwidth="62mm" colsep="1" /><colspec colnum="2" colname="col2" colwidth="12mm" colsep="1" /><tbody><row><entry namest="col1" nameend="col1" align="left" valign="top">3-chloropropyl (triethoxysilane) (GC)</entry><entry namest="col2" nameend="col2" valign="top" align="char" char="." charoff="59">0,7</entry></row><row><entry namest="col1" nameend="col1" align="left" valign="top">3-mercaptopropyl (triethoxysilane) (GC)</entry><entry namest="col2" nameend="col2" valign="top" align="char" char="." charoff="59">93,7</entry></row><row><entry namest="col1" nameend="col1" align="left" valign="top">(EtO)₃Themselves₂)₃-S- (CH₂)₃-Si (OEt)₃ (GC)</entry><entry namest="col2" nameend="col2" valign="top" align="char" char="." charoff="59">1,7</entry></row></tbody></tgroup></table></tables>Based on the above values, the conversion is&gt; 99% and the selectivity of the reaction is 98%.

Example 10:

36.2 g of dried NaSH and 800 ml of dry ethanol are placed in an autoclave with a double glass jacket and Hastelloy C22 lid + fittings (Buechi AG) at room temperature and stirred at 70-73 ° C. for 15 min. A mixture of 100 g of 3-chloropropyl (triethoxysilane) and 20 g of a silane mixture of 3-chloropropyl (diethoxy (chloro) silane), 3-chloropropyl (ethoxy (dichloro) silane), 3-chloropropyl (trichlorosilane) and 3- Chloropropyl (triethoxysilane) was added to the suspension with a pressure burette. The 20 g are taken from a silane mixture which is obtained by reaction from 694.2 g of 3-chloropropyl (triethoxysilane) and 350.8 g of 3-chloropropyl (trichlorosilane). A further 200 ml of ethanol are added to the suspension via the burette, heated to 101-104 ° C. and the temperature maintained for 180 min. The mixture is then cooled to 56 ° C. and 2.6 g of formic acid in 100 ml of ethanol are metered in using a pressure burette. The mixture is stirred for 15 min and then a sample is taken. The GC analysis of the reaction mixture shows the following composition in area percent:<tables id="tabl0018" num="0018"><table frame="all"><tgroup cols="2" colsep="1" rowsep="1"><colspec colnum="1" colname="col1" colwidth="57mm" colsep="1" /><colspec colnum="2" colname="col2" colwidth="13mm" colsep="1" /><tbody><row><entry namest="col1" nameend="col1" align="left" valign="top">3-chloropropyl (triethoxysilane)</entry><entry namest="col2" nameend="col2" valign="top" align="char" char="." charoff="65">0,042</entry></row><row><entry namest="col1" nameend="col1" align="left" valign="top">3-mercaptopropyl (triethoxysilane)</entry><entry namest="col2" nameend="col2" valign="top" align="char" char="." charoff="65">5,572</entry></row><row><entry namest="col1" nameend="col1" align="left" valign="top">(EtO)₃Themselves₂)₃-S- (CH₂)₃-Si (OEt)₃</entry><entry namest="col2" nameend="col2" valign="top" align="char" char="." charoff="65">0,046</entry></row><row><entry namest="col1" nameend="col1" align="left" valign="top">(EtO)₃Themselves₂)₃-S₂- (CH₂)₃-Si (OEt)₃</entry><entry namest="col2" nameend="col2" valign="top" align="char" char="." charoff="65">0,022</entry></row></tbody></tgroup></table></tables>Based on the above values, the conversion is&gt; 99% and the selectivity of the reaction&gt; 98%.

The suspension obtained is filtered. The separated solid is washed with 400 ml of n-pentane. The solution obtained is freed from the volatile constituents at 20-600 mbar and 60-80 ° C. on a rotary evaporator. The suspension obtained is mixed well with 200 ml of pentane and stored at 4-8 ° C. for 10 h. The precipitated solid is separated off by filtration and washed with 150 ml of pentane. The pentane is removed from the clear solution obtained using a rotary evaporator at 20-600 mbar and 60-80 ° C. 111.1 g of a colorless liquid are obtained.

Analysis with GC (dodecane as internal standard) shows the following composition of the product obtained in percent by weight:<tables id="tabl0019" num="0019"><table frame="all"><tgroup cols="2" colsep="1" rowsep="1"><colspec colnum="1" colname="col1" colwidth="62mm" colsep="1" /><colspec colnum="2" colname="col2" colwidth="12mm" colsep="1" /><tbody><row><entry namest="col1" nameend="col1" align="left" valign="top">3-chloropropyl (triethoxysilane) (GC)</entry><entry namest="col2" nameend="col2" valign="top" align="char" char="." charoff="59">0,7</entry></row><row><entry namest="col1" nameend="col1" align="left" valign="top">3-mercaptopropyl (triethoxysilane) (GC)</entry><entry namest="col2" nameend="col2" valign="top" align="char" char="." charoff="59">94,9</entry></row><row><entry namest="col1" nameend="col1" align="left" valign="top">(EtO)₃Themselves₂)₃-S- (CH₂)₃-Si (OEt)₃ (GC)</entry><entry namest="col2" nameend="col2" valign="top" align="char" char="." charoff="59">1,7</entry></row></tbody></tgroup></table></tables>Based on the above values, the conversion is&gt; 99% and the selectivity of the reaction is 98%.