Synthesis of diastereomeric pheromones: adjacent methyl-branched alcohols and ketones

Racemic synthesis of adjacent methyl-branched alcohol and ketone pheromones is particularly considered for large scale trap of insects due to their similar activity to the chiral components in field trial. In this work, we presented a straightforward and effective strategy for racemic synthesis of adjacent methyl-branched alcohols to obtain the different diastereomer rates (threo: erythreo = 2:1 and 1:1) via Felkin-Anh model. No effect of alkyl chain lenth on stereoselectivity of adduct has been demonstrated. Moreover, the α-methyl ketones were effectively produced by microwave-assisted oxidation of the respective secondary alcohols using 2-iodoxybenzoic acid (IBX)