10.1021/ja057741q.s001 Yike Ni Yike Ni John Montgomery John Montgomery Synthetic Studies and Mechanistic Insight in Nickel-Catalyzed [4+2+1] Cycloadditions American Chemical Society 2006 sequence divinylcyclopropane evidence diene cycloaddition Stereochemical studies mechanism stereoselectivitie trimethylsilyl substrate alkyne Synthetic Studies sigmatropic rearrangement Mechanistic Insight Cycloaddition procedure 2006-03-01 00:00:00 Journal contribution https://acs.figshare.com/articles/journal_contribution/Synthetic_Studies_and_Mechanistic_Insight_in_Nickel_Catalyzed_4_2_1_Cycloadditions/3235945 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.