Alkynylcyanation of alkynes and dienes catalyzed by nickel

Alkynyl cyanides are found to add across alkynes and 1,2-dienes in the presence of a catalyst prepared in situ from Ni(cod)2, xantphos, and BPh3. A range of functionalized conjugated cis-enynes are obtained with high regioselectivity. The addition reaction across norbornadiene proceeds in the absence of BPh3 to give exo-cis adduct exclusively. A stoichiometric reaction of an alkynyl cyanide, Ni(cod)2, xantphos, and BPh3 gives trans-(xantphos)Ni(CNBPh3)(CCSiMe2t-Bu), which is suggested to be a plausible reaction intermediate of the alkynylcyanation reaction.

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