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:
Sep. 07, 1982
Filed:
Mar. 11, 1981
Philip N Edwards, Stockport, GB;
David M Martin, Stockport, GB;
Imperial Chemical Industries Limited, London, GB;
Abstract
The invention is concerned with novel dioxolane derivatives of the formula: ##STR1## in which R.sub.a is hydrogen or (1-4C)alkyl and R.sub.b is (1-4C)alkyl or phenyl optionally bearing a halogeno substituent; their production; and their use for the manufacture of certain known anti-arthritic acids of the formula: ##STR2## and, in particular, those acids in which R.sub.a =R.sub.b =methyl or R.sub.a =ethyl and R.sub.b =phenyl, by a novel reduction process. The preferred reduction procedures involve the use of an alkali metal borohydride or cyanoborohydride in the presence of a noble metal catalyst, or the use of an .alpha.-branched alkyl or cycloalkyl Grignard agent. The use of the derivatives of formula I avoids the need for potentially toxic reagents and reactive intermediates in the previously known processes for the production of the acids of formula V.