A Facile Alkylation of Aryl Aldehyde Tosylhydrazones with Trialkylboranes

Trialkylboranes readily alkylate aryl aldehyde tosylhydrazones to produce either the corresponding arylalkene or aryl alcohol in excellent yields. The authors wish to report an alkylation reaction utilizing trialkylboranes that is equivalent to the overall 1,2-addition of an alkyl group to a carbonyl compound. Tributylborane reacts with aryl aldehyde tosylhydrazones in the presence of base to produce a new trialkylborane. This trialkylborane is readily protonolyzed to the corresponding alkane 2 or oxidized to the corresponding alcohol 3 depending upon the reaction condition chosen.