PROCESSO DE REDUCAO CATALITICA DE COMPOSTOS ALCINO

摘要

A process is provided for the preparation of cyclohexene derivatives of general formula I or II:in which the substituents R<1 >and R<2 >independently of one another are defined as follows:R<1 >isR<2 >is OH or a protective group convertible to a hydroxyl group by hydrolysis;R<3 >and R<4 >are hydrogen or C1-C4-alkyl; andR<5 >is hydrogen or C1-C4-acyl,by the reduction of alkyne compounds of general formula III or IV:in which the substituents R<1 >and X are as defined above, wherein the reducing agent used is a mixture of zinc and at least one compound B selected from the group consisting of ammonium salts, copper salts and alkali metal and alkaline earth metal salts.