Mechanistic Implications of Nickel-Catalyzed Reductive Coupling of Aldehydes and Chiral 1,6-Enynes

Organic Letters 8(3), 455-458, DOI: 10.1021/ol052719n

A study of nickel-catalyzed reductive coupling reactions of aldehydes and chiral 1,6-enynes has provided evidence for three distinct mechanistic pathways that govern regioselectivity in this transformation. In the absence of a phosphine additive, high regioselectivity and high diastereoselectivity are obtained as a direct result of coordination of both the alkyne and the olefin to the metal center during the C−C bond-forming step.