WO2008009680A1

WO2008009680A1 - Novel hydrogen-rich 1,3-dialkoxydisiloxanes and processes for their preparation and their use

Info

Publication number: WO2008009680A1
Application number: PCT/EP2007/057379
Authority: WO
Inventors: Gerrit Fester; Gerhard Roewer; Edwin Kroke
Original assignee: Technische Universität Bergakademie Freiberg
Priority date: 2006-07-17
Filing date: 2007-07-17
Publication date: 2008-01-24
Also published as: DE112007001661A5

Abstract

The present invention relates to novel hydrogen-rich 1,3-dialkoxydi-siloxanes and 1,3-dialkylthiodisilathianes of the (R1A)H2SiASiH2(AR2) type where A = O or S and R1 and R2 are each independently selected from tertiary radicals, and to processes for their preparation and to their use for hydrosilylation, for producing coatings, as sealants and additives, and as defined starting molecules in polymerization reactions, as polymer or adhesive additives, in coatings, and in the building materials industry or in the protection of buildings.

Description

New hydrogen-rich 1,3-dialkoxy-disiloxanes and process for their preparation and their

use

The present invention relates to novel hydrogen-rich 1,3-dialkoxy-disiloxanes, in particular of the type (RO) H ₂ SiOSiH ₂ (OR), and to processes for their preparation and their use. These novel 1,3-dialkoxy-disiloxanes can be used, for example, in hydrosilylation, as precursor compounds in building protection, as sealants and additives and as defined starting molecules in polymerization reactions.

The previously practiced syntheses of alkoxysilane compounds lead both by controlled and by uncontrolled substitutions of an Si-Cl bond exclusively to the alkoxysilane.

Hensen et al. First described the formation of dichlorosilane-pyridine adducts in the reaction of dichlorosilane with pyridine [K. Hensen et al, J. Am. Chem. Soc. 120 (1998) 10402]:

This adduct is very reactive and decomposes on contact with the slightest traces of water. Thermally, the adducts also decompose easily. Because of this, the class of compounds has hitherto not been included in any application to the knowledge of the inventors.

A process for the preparation of the hydrogen-rich 1,3-dialkoxy-disiloxanes of the type (RO) H ₂ SiOSiH ₂ (OR) is not mentioned in the literature so far.

US 2004137758 describes a method for depositing a film with a low dielectric constant. The process should be used in addition to a variety of other aliphatic organosilicon compounds, 1,3-dimethyldimethoxysiloxane. However, nothing is said here about a possible synthesis of the compound.

Due to the four hydrogen atoms in the molecule, a synthesis of 1,3-dialkoxy-disiloxanes of the type (RO) H ₂ SiOSiH ₂ (OR) is very demanding, since reactions in the basic or strongly acidic medium can lead to the cleavage of silicon-hydrogen bonds ,

It is therefore an object of the invention to provide novel 1,3-dialkoxy-disiloxanes, in particular the general formula (RO) H ₂ SiOSiH ₂ (OR), and to provide a process for their preparation. According to the invention the object is achieved by new hydrogen-rich 1,3-dialkoxy-disiloxanes of the general formula

(R ¹ A) H ₂ Si-A-SiH ₂ (AR ² )

(Formula 1) with A selected from oxygen (O) and sulfur (S).

The radicals R ¹ and R ² each represent tertiary radicals, ie the carbon of the radicals R ¹ and R ² bound to A (oxygen or sulfur) has bonds to 3 further non-hydrogen atoms, preferably three atoms selected from the elements carbon, silicon , Germanium, tin and lead. Ie. the radicals R ¹ and R ² each have the general formula:

T ³ IT ² - C-

IT ¹

(Formula 2) wherein T ¹ , T ² and T ^{3 are} each independently selected from substituted, unsubstituted, linear, branched and cyclic, saturated and unsaturated hydrocarbon radicals, silane radicals, alkoxysilane radicals, borane radicals, Carbaboranresten, German radicals, Alkoxygermanresten, stannane radicals or Plumbanresten with preferably in each case 1 to 10, preferably 1 to 6, non-hydrogen atoms, preferably selected from the elements carbon, silicon, germanium, tin and lead. T ¹ , T ² and T ³ may be identical (eg 3 methyl groups in the case of t-butyl) or different radicals. If all three radicals T ¹ , T ² and T ³ are different from one another, formula 2 encompasses both the R and the S isomer and also the corresponding racemate. Radicals R ¹ and R ² in which all radicals T ¹ , T ² and T ^{3 are} cyclic or aromatic radicals are less preferred.

Preferably, R ¹ and R ² are independently selected from substituted, unsubstituted, saturated and unsaturated tertiary hydrocarbon radicals having from 4 to 10 carbon atoms. More preferably, R ¹ and R ^{2 are} independently selected from t-butyl, 2-methylbut-2-yl, 2,3-dimethylbut-2-yl, 2,3-dimethylbut-3-yl, 2,3,3- Trimethylbut-2-yl, 2-methylpent-2-yl, 3-methylpent-3-yl, 2,3-dimethylpent-2-yl, 2,3-dimethylpent-3-yl, 2,4,4-tri methylpent-2-yl, 3-ethylpent-3-yl, 3-ethylbut-3-yl, 3-ethyl-2-methylpent-3-yl, 3-ethyl-2-methylpent-2-yl, 3 Methylhex-3-yl, 3-methylhept-3-yl, 4-methylhept-4-yl, 2,4,4,6,6-pentamethylhept-2-yl, 2-methyloct-2-yl, t-octyl, 5-butylnon-5-yl, t-tetradecyl, 2,3-dimethyldecyl, t-dodecyl, 3-methyl-3-tetradecyl, 4-ethenyl-3-ethyloct-3-yl, 3-methyldodec-3-yl, 4-methyltridec-4-yl, 6-methylpentanedec-6-yl, 2,2,3,5,5-pentamethylhex-3-yl, 2-methylhexadeca-2-yl, 2,4-dimethylnon-4-yl, 3-methyl-5-hexen-3-yl, 3,5-dimethyl-5-hexen-3-yl, 4- (2-methylpropyl) -l, 6-heptadien-4-yl, 4- (2-propenyl ) -l, 6- heptadien-4-yl, 1-methylcyclopentyl, 1-methylcyclopentyl, 1-methylcyclohexyl, 1-ethylcyclohexyl, 1-propylcyclopentyl, 1-methylcyclohex yl, 1-ethylcyclohexyl, 1-propylcyclohexyl, 1-methyl cycloheptyl, 1-ethylcycloheptyl, 1-propylcycloheptyl, bicyclo [2.2.2] octan-1-yl, norbornyl, adamantyl, 3-methyl-1-adamantyl and 3-i-propyl-1-adamantyl.

Preferred compounds according to the invention are compounds with R ¹ = R ² = R, in particular 1,3-dialkoxy-disiloxanes of the general formula (RO) H ₂ SiOSiH ₂ (OR) where R = t-butyl, 2-methylbut-2-yl, 3-methylpent-3-yl, 3-ethylpent-3-yl, 3-ethylbut-3-yl, 3-methylhex-3-yl, 3-methylhept-3-yl.

According to the invention the new compounds of the type (R ¹ A) H ₂ Si-A-SiH ₂ (AR ² ) are prepared with A = O or S such that a.) A dihalosilane of the type H ₂ SiX ₂ with X = halogen and b.) a tertiary alcohol or tertiary thiol, c.) are reacted with an excess of a tertiary amine (eg an aliphatic trialkylamine) or a cyclic aromatic amine in an aprotic solvent or solvent-free.

As tertiary alcohol (A = O) or tertiary thiol (A = S) is either a mixture of tertiary alcohols (or tertiary thiols) of the general formulas R ¹ AH and R ² AH or for the synthesis of compounds with R ¹ = R ² = R is an alcohol (or tertiary thiol) of the general formula HAR, wherein R is preferably an alkyl radical having at least 3 carbon atoms. The use of a tertiary alcohol (or thiol) is important because with primary or secondary alcohols (or thiols) di- or Trialkoxysilane are formed, ie compounds containing only one silicon.

R ¹ and R ² (or R in the case where R ¹ = R ² = R) are as selected above, d. h the tertiary alcohol or the tertiary thiol has the following general formula:

^" P

IT ² - CA H

IT ¹

(Formula 3) with A = O or S. T ¹ , T ² and T ³ are selected from the radicals mentioned above for formula 2 If all three radicals T ¹ , T ² and T ³ are different from each other, formula 3 comprises both the R - As well as the S-isomer and the corresponding racemate.

The alcohols are preferably selected from t-butanol, 2-methylbutan-2-ol, 3-methylpentan-3-ol, 3-ethylpentan-3-ol, 2-methylpentan-2-ol, 2,3-dimethylpentan-3 ol, 2,3,3-trimethylbutan-2-ol, 3-ethyl-2-methylpentan-3-ol, 5-butylnonan-5-ol, 4-methylheptan-4-ol, 2,4,4-trimethylpentane 2-ol, 3-methyl-5-hexen-3-ol, 3,5-dimethyl-5-hexen-3-ol, 2,3-dimethyldecanol, 3-methyl-3-tetradecanol, 4-ethenyl-3-ol ethyloctan-3-ol, 3-methyldodecan-3-ol, 4-methyltridecan-4-ol, 6-methylpentanecane-6-ol, 2,2,3,5,5-pentamethylhexan-3-ol, 2-methylhexadeca 2-ol, 2,4-dimethylnonan-4-ol, 4- (2-methylpropyl) -1, 6-heptadien-4-ol, 1-methylcyclopentanol, 1-ethylcyclohexanol, 1-propylcyclopentanol, 1-methylcyclohexanol, 1-ethylcyclohexanol, 1-propylcyclohexanol, 1-methylcycloheptanol, 1-ethylcycloheptanol, 1-propylcycloheptanol, 1-adamantol, bicyclo [2.2.2] octan-1-ol, 3-methyl-1-adamantol and 3-i-propyl-1-adamantol.

The thiols are preferably selected from t-butylthiol (t-butylmercaptan), t-octylmercaptan, 2-methyl-2-pentanethiol, 2,3-dimethyl-2-butanethiol, 2-methyl-2-butanethiol, t-dodecylmercaptan, 2 , 4,6,6,6-Pentamethyl-2-heptanethiol, 2-methyl-2-octathiol, 4- (2-propenyl) -1,6-heptadiene-4-thiol and t-tetradecylmercaptan.

The inventors have in the experiment to produce di- (t-butoxy) silane, discovered to their surprise that the reaction of dihalosilane with tertiary alcohols or thiols to hitherto unknown hydrogen-rich dialkyldisiloxanes such. As 1,3-di-t-butoxydisiloxanen leads.

The reaction of tertiary alcohols (or thiols) with a dihalosilane, such as dichlorosilane, with addition of a tertiary amine (for example of trialkylamines in the ratio 1: 2) or a cyclic aromatic amine surprisingly results in hitherto unknown hydrogen-rich dialkoxydisiloxanes, such as. B. 1,3-di-t-butoxydisiloxane. The use of an excess of a tertiary amine such. For example, trialkylamine (i.e., eg, from 3 to 4.5 moles of auxiliary nitrogen atoms per mole of dihalosilane) advantageously allows selective synthesis of the desired hydrogen-rich 1,3-dialkoxy-disiloxane of formula (4):

2 H ₂ SiCl ₂ + 3 HAR + 3 NFT ₃ ► (RA) H ₂ SiASiH ₂ (AR) + 3 NR ^' ₃ ^* HCl + RCI

(Formula 4) R is a tertiary group and preferably selected as mentioned above.

NR ' ₃ is a tertiary amine and is preferably selected as mentioned above, ie radicals R' can also represent different radicals or together form a cyclic radical.

The formed organylammonium chloride (in simplified form represented as NR ' ₃ * HCl) can advantageously be readily separated from the solution as a solid. For the synthesis of the compounds according to the invention, in particular the hydrogen-rich 1,3-dialkoxy-disiloxanes, preference is given to direct conversion with dichlorosilane, the weaker basic compounds from triethylamine (Et ₃ N, pK _B 3.24), trimethylamine (Me ₃ N , pK _B 4.26), ethyldipropylamine (Et (n-Pr) ₂ N) and diethylpropylamine (Et ₂ (n-Pr) N) -containing group and 1,4-diaza-bicyclo [2.2.2] octane (N ( C ₂ FLi) ₃ N, CAS #: 280-57-9, also TED - triethylenediamine called) is used.

Other preferred tertiary amines are the aliphatic tertiary amines tributylamine and 1,1,3,3-tetramethylguanidine (TMG, CAS #: 80-70-6) and the non-aromatic cyclic tertiary amines 1,2,2,6,6 Pentamethylpiperidines (pempidine, CAS #: 79-55-0), 1-azabicyclo [2.2.2] octane (Quinuclidine, CAS #: 100-76-5), l, 5,7-triazabicyclo (4.4.0) dec-5-ene (TBD, CAS #: 5807-14-7), 7-methyl-1, 5 , 7-triazabicyclo (4.4.0) dec-5-ene (MTBD, CAS #: 84030-20-6), 1,5-diazabicyclo [4.3.0] - non-5-ene (DBN, CAS #: 3001 -72-7) or l, 8-diazabicyclo [5.4.0] undec-7-ene (DBU, CAS #: 6674-22-

2).

The compounds produced, in particular the hydrogen-rich 1,3-dialkoxy-disiloxanes of the (RO) H ₂ SiOSiH ₂ (OR) type, are advantageously stable in solution over a relatively long period of time. The synthesis can be carried out with a quantitative yield, based on the dichlorosilane used.

Another novel way to get to the desired hydrogen-rich 1,3 dialkoxy disiloxanes is the use of more highly coordinated compounds of the type H ₂ SiX ₂ * 2 B. Here, B is a substituted or unsubstituted aromatic amine

In such a complex, preferably, two molecules of the aromatic amine B are coordinated with one molecule of dihalosilane H ₂ SiX ₂ . The structure of the complex is explained below with reference to the example of a complex of dichlorosilane and 2 pyridines or pyridines substituted with R ³ (eg methyl or chlorine):

(Formula 5)

By coordination with 2 molecules of aromatic amine, such as. Pyridine, the silicon-halogen bond is extended, i. the reactivity of this bond increases.

Preferably, the dihalosilane with the aromatic amine forms 1: 2 complexes (one molecule each of dihalosilane, preferably dichlorosilane, and 2 molecules of aromatic amine, such as pyridine).

These higher coordinated compounds can be prepared directly from the dihalosilane, preferably dichlorosilane, and the aromatic amine, such as. B. substituted pyridines are generated and then reacted directly with the tertiary alcohol (or thiol), a purification of the higher coordinated products is not required.

The conversion of the higher-coordination silicon compound thus produced with tertiary alcohols (or thiols) of the HAR type with A = O or S and R = tertiary alkyl leads surprisingly exclusively to the hydrogen-rich 1,3-dialkoxy-disiloxanes or the corresponding sulfur-containing compounds according to the invention (1,3-dialkylthio-disilathiane). This is illustrated by a pyridine (PyR ³ ) substituted with R ³ (eg, methyl or chlorine) as an example of a cyclic aromatic amine B and dichlorosilane as an example of a dihalosilane - s. Formula 6.

- -R

(Formula 6)

It is important that compounds of the type H ₂ SiX ₂ * 2 B are used, but particularly preferably compounds of the type H ₂ SiCl ₂ * 2 B. For the reaction, it is less of interest whether B = pyridine, methyl, Ethyl, t-butyl, vinyl, dimethylamino or a halo-pyridine. For the alcoholysis reaction, the presence of reactive silicon-chlorine bonds is crucial. The use of compounds of the type [H ₂ SiB ₄ ] Cl ₂ (B = substituted pyridines) does not lead to the desired 1,3-dialkoxy-disiloxane.

Preferably, the aromatic amine B is a nitrogen-containing heteroaromatic having a maximum of 1 hydrogen atom on the N atom, preferably no hydrogen atom on the N atom, preferably pyridine or a substituted pyridine, for. B. selected from the group of alkyl- or halogen-substituted pyridines, such as. As the picolines (2-methyl, 3-methyl, 4-methyl-pyridine), the lutidines (2,3-, 2,4-, 2,5-, 3,4-, and 3,5- Dimethyl pyridine), the collidines (2,3,5- and 2,3,6-tri-methylpyridine), or corresponding ethyl, propyl, t-butyl, pentyl, hexyl, vinyl, phenyl, pyridyl, , Naphthyl, cyclohexyl (e.g., 4-t-butyl or 4-vinylpyridine), the bromine-substituted pyridines, and the dialkyl-amine-substituted pyridines, such as. As 4-dimethylamino-pyridine or 4-diethylaminopyridine or pyrimidine or pyrazine or a correspondingly substituted pyrimidine or pyrazine. Pyridines, pyrimidines or pyrazines which are substituted in the 2 and 6 positions (that is, for example, 2,6-lutidine and the 2,4,6-collidine) are less preferred because they lead to the dismutation of the dichlorosilane and no higher coordination Form connections. The type and site of substitution on pyridine, pyrimidine or pyrazine is otherwise not critical to the reaction. When using an aromatic amine B, this is preferably initially charged with the dihalosilane before the tertiary alcohol is added, so that initially a coordination complex of the amine and the dihalosilane can be formed.

This reaction can be carried out both in a solvent and without a solvent. For better handling and purification of the products, however, the synthesis is preferably carried out in an aprotic solvent. Preferred solvents are mentioned later in the text. The reaction is preferably carried out with cooling or, in particular in the case of the substituted pyridines, pyrimidines or pyrazines, at room temperature.

As dihalosilane preferably dichlorosilane H ₂ SiCl ₂ and less preferably also dibromosilane H ₂ SiBr ₂ are used. Dichlorosilane is produced in large quantities for the semiconductor industry and is therefore advantageously an inexpensive starting material. It is preferable to use 20 mmol of H ₂ SiCl ₂ per 5 ml to 100 ml of solvent, preferably 15 ml to 25 ml of solvent.

Preferred solvents for the reaction are aprotic solvents, such as toluene, n-hexane, cyclohexane, n-pentane, n-heptane, petroleum ether, tetrahydrofuran, diethyl ether, ethyl acetate, dioxane, glyme and mixtures of these solvents. In order to avoid side reactions, the solvent is preferably anhydrous and preferably has a maximum water content of less than 0.1%, particularly preferably of not more than 0.01%.

In order to ensure an even better control of the reaction, the process is carried out under cooling, preferably at a temperature of -80 to + 40 ⁰ C, preferably - 70 to +10 ⁰ C, more preferably -20 ⁰ C to +5 ⁰ C. , Since the reaction is exothermic, the reaction mixture is cooled to the appropriate temperature, preferably with an ice bath or an alcohol / dry ice mixture.

Despite the low temperatures, the reactions run off very rapidly, within 15 to 60 minutes.

The tertiary alcohols used are most preferably alcohols which can exchange the hydroxy substituents for a chloride substituent in a substitution reaction. In the intermediate step, a stabilized secondary or preferably tertiary carbenium ion is formed.

(Formula 7)

The individual released water molecules seem to be crucial for the selective formation of the hydrogen-rich 1,3-dialkoxy-disiloxane. In order to control the reaction to allow easier is preferably carried out with cooling of the reaction mixture, the synthesis, as advantageously a temperature range from -80 ⁰ C to +40 ⁰ C has proven to be.

The invention further relates to the use of the compounds according to the invention for hydrosilylation, for the production of coatings, as sealants and additives and as defined starting molecules in polymerization reactions, as polymer or adhesive additives, in paints, and in the building materials industry or in building protection. Another use of the compounds according to the invention, in particular the 1,3-dialkylthio-disilathiane, is the purification of silicon, since their decomposition pure silicon can be formed.

The invention will be explained in more detail below by means of exemplary embodiments:

All reactions were carried out under protective gas using the Schlenk technique. Commercially available starting materials were used and dried according to laboratory instructions.

Embodiment 1: Preparation of 1,3-di-t-butoxy-disiloxane from dichlorosilane:

2 H ₂ SiCl ₂ + 3 ¹ C ₄ H ₉ OH + 3 N (C ₂ H ₅ ) ₃ ► (C ₄ H ₉ O) H ₂ SiO SiH ₂ (OC ₄ H ₉ )

1

+ 3N (C ₂ H ₅ ) ₃ * HCl + ¹ C ₄ H ₉ Cl

4.23 ml (20 mmol) of a 40% dichlorosilane-toluene solution under isopropanol / dry-ice cooling together with 40 ml of toluene are placed in a Schlenk vessel with magnetic stir bar. 8.08 g (80 mmol) of triethylamine are added to this solution. By means of a syringe 3.71 g (50 mmol) of t-butanol, dissolved in 5 ml of toluene, slowly added dropwise over a period of 5 min. Immediate formation of white triethylammonium chloride occurs. After completion of the evolution of gas, the reaction mixture is slowly warmed to room temperature and the resulting solid was separated by means of a Schlenk frit. The yield measured on the resulting triethylamine hydrochloride is over 90%.

The solid is then washed with 30 ml of toluene and dried in vacuo. The reaction solution is characterized by NMR spectroscopy. The solution contained only 1,3-di-t-butoxy-disiloxane (1): NMR data:

²⁹ Si NMR: δ ((H ₂ Si (O ^t C ₄ H ₉ )) ₂ θ) = -50.99 ppm

H-NMR: δ ((H ₂ Si (O ^t C ₄ H ₉ )) ₂ θ) = 5.06 ppm,

6 ((H ₂ Si (O ¹ C ₄ HjO) ₂ O) = 1.45 ppm

The NMR data show that the desired compound 1,3-di-t-butoxy-disiloxane is present in a purity of more than 95%.

Embodiment 2: Preparation of 1,3-di-t-butoxy-disiloxane from H ₂ SiCl? * 2 pyridine:

First, a solution of dichlorosilane in pyridine is prepared as follows:

4.23 ml (20 mmol) of a 40% dichlorosilane / toluene solution under isopropanol / dry ice cooling together with 40 ml of toluene are placed in a Schlenk flask (100 ml) with magnetic stir bar. To this solution 3.24 g (41 mmol) of pyridine are added, it comes immediately to the formation of a white precipitate of the resulting product. After completion of the product precipitation, the reaction mixture is slowly warmed to room temperature and the resulting solid is separated by filtration with a Schlenk frit and dried.

The complexed dichlorosilane is referred to below as di-pyridine-dichlorosilane or H ₂ SiCl ₂ * 2 pyridine.

- -O

In a Schlenk vessel with magnetic stir bar 1.56 g (6 mmol) of H ₂ SiCl ₂ * 2 pyridine are presented under isopropanol / dry ice cooling together with 20 ml of toluene. By means of a syringe 0.89 g (12 mmol) of t-butanol, dissolved in 5 ml of toluene, slowly added dropwise over a period of 5 min. This reaction mixture is stirred for 1 h. Thereafter, the reaction mixture is slowly warmed to room temperature and the resulting solid is separated by means of a Schlenk frit. The yield is over 90%.

The solid is then washed with 10 ml of toluene and dried in vacuo. The reaction solution is characterized by NMR spectroscopy. The solution contained only 1,3-di-t-butoxy-disiloxane (2):

NMR data:

²⁹ Si-NMR: δ ((H ₂ Si (O ^t C ₄ H ₉ ) ₂ θ) -51.01 ppm 1 H-NMR: δ ((H ₂ Si (O ^t C ₄ H ₉ )) ₂ θ) 5.07 ppm δ ((H ₂ Si (O ^t C ₄ H 9) ₂ θ) 1.43 ppm

¹³ C-NMR: δ ((H ₂ Si (OC (CH ₃ ) S) ₂ O) 73.14 ppm δ ((H ₂ Si (OC (CH ₃ ) ₃ ) ₂ O) 31.15 ppm

The NMR data show that the desired compound is di-t-butoxy-disiloxane in a purity greater than 95%.

Embodiment 3: Preparation of 1,3-bis (2-methyl-2-butoxy) -disiloxane from H ₂ SiCl? * 2 pyridine:

2 - O-

In a Schlenk vessel with a magnetic stir bar 1.87 g (7.2 mmol) of H ₂ SiCl ₂ * 2 pyridine (see Example 2) under isopropanol / dry ice cooling, together with 20 ml of toluene. By means of a syringe, 1.91 g (21.7 mmol) of 2-methyl-2-butanol are slowly added dropwise over a period of 5 min. This reaction mixture is stirred for 1 h. Thereafter, the reaction mixture is slowly warmed to room temperature and the resulting solid is separated by means of a Schlenk frit. The yield is over 90%.

The solid is then washed with 10 ml of toluene and dried in vacuo. The reaction solution is characterized by NMR spectroscopy. The solution contains only 1,3-bis (2-methyl-2-butoxy) -disiloxane (3): NMR data:

²⁹ Si NMR: δ ((H ₂ Si (2-methyl-2-butoxy)) ₂ O) -51.04 ppm 1 H-NMR: δ ((H ₂ Si ((CH ₃ ) ₂ (C ₂ H ₅ ) CO)) ₂ θ) 5.09 ppm δ ((H ₂ Si ((CH ₃ ) ₂ (C ₂ H ₅ ) CO)) ₂ θ) 1.43 ppm δ ((H ₂ Si ((CH ₃ ) ₂ (CH ₂ CH 3) CO)) ₂ O) 1.69 ppm δ ((H ₂ Si ((CH ₃ ) ₂ (CH ₂ CH ₃ ) CO)) ₂ O) 1.22 ppm

The NMR data show that the desired compound is l, 3-bis (2-methyl-2-butoxy) -disiloxane in greater than 95% purity.

Embodiment 4: Preparation of 1,3-di-t-butyrthia-disilathiane from H ₂ SiCl? * 2 pyridine:

2 -

In a Schlenk vessel with magnetic stir bar, 1.87 g (7.2 mmol) of H ₂ SiCl ₂ * 2 pyridine (see Embodiment ₂ ) are initially charged under isopropanol / dry ice cooling. By means of a syringe, 1.95 g (21.7 mmol) of t-butyl mercaptan are slowly added dropwise over a period of 5 min. This reaction mixture is stirred for 1 h. Thereafter, the reaction mixture is slowly warmed to room temperature and the resulting solid is separated by means of a Schlenk frit. The yield is over 90%.

The solid is then washed with 10 ml of toluene and dried in vacuo. The reaction solution is characterized by NMR spectroscopy. The solution mainly contains 1,3-di-t-butylthio-disilathiane (4):

NMR data:

²⁹ Si-NMR: δ ((H ₂ Si (S ^t C ₄ H ₉ ) ₂ S) = -48.7 ppm 1 H-NMR: δ ((H ₂ Si (S ^t C ₄ H ₉ )) ₂ S ) = 5.02 ppm, δ ((H ₂ Si (S ¹ C ₄ H ₉ X) ₂ S) = 1.95 ppm

³ C-NMR: δ ((H ₂ Si (SC (CH ₃ ) ₃ ) ₂ S) = 41, 6 ppm δ ((H ₂ Si (SC (CH ₃ ) ₃ ) ₂ S) = 35.2 ppm The NMR data show that the desired compound 1,3-di-t-butylthia-disilathiane is present in a purity of more than 95%.

Claims

claims

1. New hydrogen-rich compounds of the general formula (R ¹ A) H ₂ Si-A-SiH ₂ (AR ² ) with A = O or S, and R ¹ and R ² , which are independently selected from tertiary radicals of the general formula :

T ³ IT ² - C-

IT ¹ where T ¹ , T ² and T ^{3 are} each independently selected from hydrocarbon radicals, silane radicals, alkoxysilane radicals, borane radicals, Carbaboranresten, German radicals, alkoxy germanresten, stannane radicals or Plumbanresten.

2. Compounds according to claim 1, wherein R ¹ and R ^{2 are} independently selected from t-butyl, 2-methylbut-2-yl, 2,3-dimethylbut-2-yl, 2,3-dimethylbut-3-yl, 2 , 3,3-trimethylbut-2-yl, 2-methylpent-2-yl, 3-methylpent-3-yl, 2,3-dimethylpent-2-yl, 2,3-dimethylpent-3-yl, 2,4 , 4-trimethylpent-2-yl, 3-ethylpent-3-yl, 3-ethylbut-3-yl, 3-ethyl-2-methylpent-3-yl, 3-ethyl-2-methylpent-2-yl, 3 -Methylhex-3-yl, 3-methylhept-3-yl, 4-methylhept-4-yl, 2,4,4,6,6-pentamethylhept-2-yl, 2-methyloct-2-yl, t-octyl , 5-Butylnon-5-yl, t-tetradecyl, 2,3-dimethyldecyl, t-dodecyl, 3-methyl-3-tetradecyl, 4-ethenyl-3-ethyloct-3-yl, 3-methyldodec-3 -yl, 4-methyltridec-4-yl, 6-methylpentaned-6-yl, 2,2,3,5,5-pentamethylhex-3-yl, 2-methylhexadeca-2-yl, 2,4-dimethylnon-4 -yl, 3-methyl-5-hexen-3-yl, 3,5-dimethyl-5-hexen-3-yl, 4- (2-methylpropyl) -1,6-heptadien-4-yl, 4- (4-yl) 2-propenyl) -1,6-heptadien-4-yl, 1-methylcyclopentyl, 1-methylcyclopentyl, 1-methylcyclohexyl, 1-ethylcyclohexyl, 1-propylcyclopentyl, 1 Methylcyclohexyl, 1-ethylcyclohexyl, 1-propylcyclohexyl, 1-methylcycloheptyl, 1-ethylcycloheptyl, 1-propylcycloheptyl, bicyclo [2.2.2] octan-1-yl, norbornyl, adamantyl, 3-methyl-1-adamantyl and 3-i-propyl-1-adamantyl.

3. Novel 1,3-dialkoxy-disiloxanes according to claim 1 or 2 having the formula (RO) H ₂ SiOSiH ₂ (OR) where R = t-butyl, 2-methyl-2-butyl, 3-methyl-3-pentyl , 3-ethyl-3-pentyl, -ethyl-3-butyl, 3-methyl-3-hexyl, or 3-methyl-3-heptyl.

4. A process for the preparation of compounds according to any one of claims 1 to 3, characterized in that a.) A dihalosilane of the type H ₂ SiX ₂ with X = halogen and b.) A tertiary alcohol or tertiary thiol with c.) An excess on a tertiary amine or a cyclic aromatic amine in an aprotic solvent or solvent-free.

5. The method according to claim 4, characterized in that 3 to 4.5 molar equivalents of trialkylamine per mole of dihalosilane are added.

6. The method according to claim 4 or 5, characterized in that the amine is selected from trimethylamine, triethylamine, ethyldipropylamine, diethylpropylamine, tributylamine, 1, 2,2,6,6-pentamethylpiperidines, 1-azabicyclo [2.2.2] octanes, Diazabicyclo [2.2.2] octane, l, 5,7-triazabicyclo [4.4.0] dec-5-ene, 7-methyl-l, 5,7-triazabicyclo [4.4.0] dec-5-ene, 1, 5-diazabicyclo [4.3.0] non-5-ene and l, 8-diazabicyclo [5.4.0] undec-7-ene.

7. The method according to claim 4, characterized in that from the dihalosilane and the cyclic aromatic amine is first prepared a compound of the type H ₂ SiX ₂ * 2 B with X = halogen, where B is the cyclic aromatic amine and the thus prepared Compound is reacted directly with a tertiary alcohol or tertiary thiol.

8. The method according to claim 4 or 7, characterized in that is used as the cyclic aromatic amine pyridine, an alkyl, dialkylamino or halogeno-pyridine.

9. The method according to claim 8, characterized in that the cyclic aromatic amine B of the compound of the type H ₂ SiX ₂ * 2 B is selected from pyridine, 4- (dimethylamino) -, 3-bromo, 4-ethyl-, 2 Methyl, 3-methyl, 4-methyl, 2,4-dimethyl, 4-t-butyl or 4-vinyl-pyridine and that preferably X = Cl.

10. The method according to any one of claims 4 to 9, characterized in that the dihalosilane is dichlorosilane.

11. The method according to any one of claims 4 to 10, characterized in that the tertiary alcohol or tertiary thiol is selected from compounds of the type:

T '

1 T ² - CA H i T ¹ with A = O or S, wherein T ¹ , T ² and T ^{3 are} each independently selected from substituted, unsubstituted, saturated and unsaturated hydrocarbon radicals, silane radicals, alkoxysilane radicals, borane radicals, Carbaboranresten, German radicals, Alkoxgermanresten, stannane residues or Plumbanresten.

12. The method according to any one of claims 4 to 11, characterized in that the alcohol is selected from t-butanol, 2-methylbutan-2-ol, 3-ethylbutan-3-ol, 2-methylpentan-2-ol, 3- Methylpentan-3-ol and 3-ethylpentan-3-ol 2,3-dimethylpentan-3-ol, 2,3,3-trimethylbutan-2-ol, 3-ethyl-2-methylpentan-3-ol, 5-butylnonan -5-ol, 4-methylheptan-4-ol, 2,4,4-trimethylpen- tan-2-ol, 3-methyl-5-hexen-3-ol, 3,5-dimethyl-5-hexene-3 -ol, 2,3-dimethyldecanol, 3-methyl-3-tetradecanol, 4-ethenyl-3-ethyloctan-3-ol, 3-methyldodecan-3-ol, 4-methyltridecan-4-ol, 6-methylpentanedecane-6 -ol, 2,2,3,5,5-pentamethylhexan-3-ol, 2-methylhexadeca-2-ol, 2,4-dimethylnonan-4-ol, 4- (2-methylpropyl) -1, 6 -heptadien-4-ol, 1-methylcyclopentanol, 1-ethylcyclohexanol, 1-propylcyclopentanol, 1-methylcyclohexanol, 1-ethylcyclohexanol, 1-propylcyclohexanol, 1-methylcycloheptanol, 1-ethylcycloheptanol, 1-propylcycloheptanol, 1 -Adamantol, bicyclo [2.2.2] octan-1-ol, 3-methyl-1-adamantol and 3-i-propyl-1-adamantol o in which the thiol is selected from t-butylthiol, 2-methyl-2-butanethiol, 2,3-dimethyl-2-butanethiol, 3-ethyl-3-butanethiol, 2-methyl-2-pentanethiol, 3-methyl-3- pentanethiol, 3-ethyl-3-pentanethiol, t-octylmercaptan, 2,4,4,6,6-pentamethyl-2-heptanethiol, 2-methyl-2-octathiol, t-dodecylmercaptan, t-tetradecylmercaptan and 4- (2-propenyl) -l, 6-heptadiene-4-thiol.

13. The method according to any one of claims 4 to 12, characterized in that the reaction at a temperature of -80 to 40 ⁰ C, preferably - 70 to +10 ⁰ C, is performed.