The catalytic asymmetric vinylogous Mukaiyama (CAVM) reactions of various aldehydes using either aldehyde or enolate activations are described. (C) 1999 Elsevier Science Ltd. All rights reserved.
CHOW, HAK-FUN;FLEMING, I., TETRAHEDRON LETT., 1985, 26, N 3, 397-400
作者:CHOW, HAK-FUN、FLEMING, I.
DOI:——
日期:——
Process for manufacturing polyene esters and acids
申请人:Roche Vitamins Inc.
公开号:US05763651A1
公开(公告)日:1998-06-09
A process for the manufacture of polyene esters or polyene acids comprises reacting a polyene O,O-dialkylacetal of di(O,O-dialkylacetal) with a vinylketene acetal or analogue thereof in the presence of a Lewis acid, hydrolyzing the reaction mixture depending on the vinylketene acetal used, subsequently cleaving alcohol under strongly basic conditions from the polyene derivative produced at this stage and, where the desired ester or carboxy group is still not present, performing the respective conversion. Certain intermediates in this process form a further aspect of the invention. The final products are primarily carotenoids which can be used appropriately, e.g. as colorants and pigments for foodstuffs, animal products etc.