Chemistry Letters, Vol.39, No.7, 766-767, 2010
Indium(III)-catalyzed Coupling between Alkynes and Aldehydes to alpha,beta-Unsaturated Ketones
The combined use of a catalytic amount of InX3 (X = OTf and NTf2) and 1-butanol was found to be effective in formal alkyne-aldehyde metathesis. With this catalytic system, aromatic alkynes reacted with aromatic aldehydes to give chalcones in moderate to good yields. Alkynals were efficiently converted into 5- to 7-membered cyclic compounds by intramolecular alkyne-aldehyde coupling.