Alkynylcyanation of alkynes and dienes catalyzed by nickel
摘要:
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 ail alkynyl cyanide, Ni(cod)2, xantphos, and BPh3 gives trans-(xantphos)Ni(CNBPh3)(C CSiMe(2)t-Bu), which is suggested to be a plausible reaction intermediate of the alkynylcyanation reaction. (C) 2009 Elsevier Ltd. All rights reserved.
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 ail alkynyl cyanide, Ni(cod)2, xantphos, and BPh3 gives trans-(xantphos)Ni(CNBPh3)(C CSiMe(2)t-Bu), which is suggested to be a plausible reaction intermediate of the alkynylcyanation reaction. (C) 2009 Elsevier Ltd. All rights reserved.
Cu-Catalyzed direct cyanation of terminal alkynes with AMBN or AIBN as the cyanation reagent