PREPARATION OF ALCOHOL BY CATALYTIC REDUCTION OF OXYGEN-CONTAINING ORGANIC COMPOUND USING GRIGNARD REAGENT

摘要

PURPOSE:To prepare various alcohols economically, by the catalytic reduction of an oxygen-containing organic compound such as a ketone, an ester, etc. with an inexpensive Grignard reagent using di-cyclopentadienyl titanium dichloride, etc. as a catalyst. CONSTITUTION:A Grignard reagent of formula RMgX is made to react with a compound selected from those of formula I - formula V (R, R<1>-R<3> are alkyl, cycloalkyl, aralkyl, or hetero ring; R<4> and R<5> are alkylene; R and R<1>-R<5> are not aryl or alpha,beta-unsaturated alkyl, however, they may contain substituent groups; X is halogen) in the presence of a catalytic amount of a compound of formula Cp2TiCl2 (Cp is cyclopentadienyl or its derivative) to obtain the corresponding alcohol. When the raw material is a cyclic ketone, the process can be used for asymmetric synthesis taking advantage of the high stereo selectivity, and when the raw mterial is an ester, the production ratio of the primry alcohol to the secondary alcohol can be adjusted by the proper selection of the amount of the catalyst.