Ionone preparation from 2-methyl-heptan-2-ol-6-one - by ethynylation and reaction of 3,7-di:methyl-1-octyne-3,7-diol with acetoacetic acid ester and iso-olefin alkyl ether

摘要

Conones are prepd. by ethynylation of 2-methylheptan-2-ol-b-one (I) and reaction of the obtained product with an acetoacetic acid ester and with an alkyletter of a iso-olefin, followed by treatment of the resulting mixture with an acid to give the desired ionone. The produced conones are used in perfumery and as intermediates for terpenes and pharmaceuticals, esp. intermediates for beta-conone used as starting cpd. in the industrial synthesis of vitamin A. The process gives negligible quantities of cyclopentenyl cpds and unreacted acetylenic alcohols can be recycled, to give high yields of ionomes and an improved industrial process.