The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 24, 1992
Filed:
Dec. 09, 1991
Tohru Kikuchi, Hitachi, JP;
Toshiyuki Fujita, Hitachi, JP;
Koichi Kamijima, Hitachi, JP;
Takayuki Saito, Hitachi, JP;
Hitachi Chemical Company, Ltd., Tokyo, JP;
Abstract
A process for producing (i) a 1,3-bis(dicarboxyphenyl)disiloxane derivative represented by the general formula ##STR1## wherein Rs and R's independently of one another denote methyl or phenyl or (ii) a 1,3-bis(dicarboxyphenyl)-disiloxane derivative dianhydride represented by the general formula ##STR2## wherein Rs and R's are as defined above, the process comprising coupling a Grignard reagent of halo-o-xylene with a disubstituted halosilane represented by the general formula ##STR3## wherein R and R' are as defined above and X denotes halogen, to form a dimethylphenyl(disubstituted silane) represented by the general formula ##STR4## wherein R and R' are as defined above, hydroxylating the dimethylphenyl(disubstituted silane) to form a dimethylphenyl(disubstituted hydroxysilane) represented by the general formula ##STR5## wherein R and R' are as defined above, to form a 1,3-bis(dimethylphenyl)-disilane