Synthetic Studies and Mechanistic Insight in Nickel-Catalyzed [4+2+1] Cycloadditions

2006-03-01T00:00:00Z (GMT) by Yike Ni John Montgomery
A new nickel-catalyzed procedure for the [4+2+1] cycloaddition of (trimethylsilyl)diazomethane with alkynes tethered to dienes has been developed. A broad range of unsaturated substrates participate in the sequence, and stereoselectivities are generally excellent. Stereochemical studies provided evidence for a mechanism that involves the [3,3] sigmatropic rearrangement of divinylcyclopropanes.