Abstract A method of producing tris-(trimethylsiloxy)-phenylsilane by hydrolytic reaction of trimethylchlorosilane, phenyltrichlorosilane and water, this reaction being carried out in the presence of 0.2 to 12 mols of hexamethyldisiloxane per mol of phenyltrichlorosilane, by adding an acid equilibration catalyst to the hexamethyldisiloxane before the beginning of the reaction and stirring this mixture either for 12 to 24 hours at room temperature or a shorter time at an elevated temperature which does not reach the boiling point, employing a molar ratio of trimethylchlorosilane to phenyltrichlorosilane of between 3.3: 1 and 4:1 and gradually adding the water until an excess is present and the hydrolysis is complete, is disclosed in U.S. Pat. application Ser. No. 270,741. This method is improved, according to the present invention, by using as said acid equilibration catalyst an amount, equal to 0.02 to 20 per cent by weight of the hexamethyldisiloxane, of a perfluoroalkanesulphonic acid of the formula CnF2n 1SO3H wherein n denotes an integer from 1 to 12.
IN A PROCESS FOR THE PRODUCTION OF TRIS-(TRIMETHYLSILOXY)PHENYLSILANE COMPRISING THE HYDROLYSIS OF A MIXTURE OF TRIMETHYLMONOCHLOROSILANE AND MONOPHENYLTRICHLOROSILANE WITH WATR, SAID HYDROLYSIS BEING CARRIED OUT IN THE PRESENCE OF 0.2 TO 12 MOLS OF HEXAMETHYLDISILOXANE PER MOL OF PHENYLTRICHLOROSILANE, BY ADDING AN ACID EQUILIBRATION CATALYST TO THE HEXAMETHYLDISILOXANE BEFORE THE BEGINNING OF THE REACTION AND STIRRING THIS MIXTURE EITHER FOR 12 TO 24 HOURS AT ROOM TEMPERATURE OR A SHORTER TIME AT AN ELEVATED TEMPERATURE WHICH DOES NOT REACH THE BOILING POINT, EMPLOYING A MOLAR RATIO OF TRIMETHYLCHLOROSILANE TO PHENYLTRICHLOROSILANE OF BETWEEN 3.3:1 AND 4:1 AND GEADUALLY ADDING THE WATER UNTIL AN EXCESS IS PRESENT AND THE HYDROLYSIS IS COMPLETE, THE IMPROVEMENT WHICH COMPRISES USING AS SAID ACID EQUILIBRATION CATALYST AN AMOUNT, EQUAL TO 0.02 TO 20 PER CENT BY WEIGHT OF THE HEXAMETHYLDISILOXANE, OF A PERFLUOROALKANESULFOHIC ACID OF THE FORMULA CNF2N+1SO3H WHEREIN N DENOTES AN INTEGER FROM 1 TO 12.
Claim 2
Dependent Claim
151 words
IN A PROCESS FOR THE PRODUCTION OF TRIS-(TRIMETHYLSILOXY)PHENYLSILANE COMPRISING THE HYDROLYSIS OF A MIXTURE OF TRIMETHYLMONOCHLOROSILANE AND MONOPHENYLTRICHLOROSILANE WITH WATR, SAID HYDROLYSIS BEING CARRIED OUT IN THE PRESENCE OF 0.2 TO 12 MOLS OF HEXAMETHYLDISILOXANE PER MOL OF PHENYLTRICHLOROSILANE, BY ADDING AN ACID EQUILIBRATION CATALYST TO THE HEXAMETHYLDISILOXANE BEFORE THE BEGINNING OF THE REACTION AND STIRRING THIS MIXTURE EITHER FOR 12 TO 24 HOURS AT ROOM TEMPERATURE OR A SHORTER TIME AT AN ELEVATED TEMPERATURE WHICH DOES NOT REACH THE BOILING POINT, EMPLOYING A MOLAR RATIO OF TRIMETHYLCHLOROSILANE TO PHENYLTRICHLOROSILANE OF BETWEEN 3.3:1 AND 4:1 AND GEADUALLY ADDING THE WATER UNTIL AN EXCESS IS PRESENT AND THE HYDROLYSIS IS COMPLETE, THE IMPROVEMENT WHICH COMPRISES USING AS SAID ACID EQUILIBRATION CATALYST AN AMOUNT, EQUAL TO 0.02 TO 20 PER CENT BY WEIGHT OF THE HEXAMETHYLDISILOXANE, OF A PERFLUOROALKANESULFOHIC ACID OF THE FORMULA CNF2N+1SO3H WHEREIN N DENOTES AN INTEGER FROM 1 TO 12.
Claim 3
Dependent Claim
24 words
A process according to claim 1, wherein said perfluoroalkanesulphonic acid is selected from the group consisting of perfluoromethanesulphonic acid, perfluorobutanesulphonic acid and perfluorooctanesulphonic acid.
Claim 4
Dependent Claim
53 words
A process according to claim 1, wherein the mixture of hexamethyldisiloxane and perfluoroalkanesulphonic acid is warmed to 50* C for about 30 minutes, the phenyltrichlorosilane is gradually added thereto, the trimethylchlorosilane is added at 30* C and finally the water is stirred in at room temperature over the course of a prolonged period.