Synthesis of tertiary acyloins using acyl anions formed from 1,3-dithians. Total synthesis of (±)-(2E)-1,7-dihydroxy-3,7,11-trimethyl-dodeca-2,10-dien-6-one

An advantageous approach for the synthesis of tertiary acyloins has been studied. The results were used in designing a successful synthesis of (±)-(2E)-1,7-dihydroxy-3,7,11-trimethyldodeca-2,10-dien-6-one (18). This acyloin was synthesized by alkylation of 2-acyl-1,3-dithians (7a and b) with (2E)-5-iodo-3-methylpent-2-en-1-ol tetrahydropyranyl ether (10). The synthesis of the key intermediate (10) is reported. This type of modified farnesol can be used for investigating the biosynthetic intermediates of natural substances.