Preparation of polyfunctional nitriles by the cyanation of functionalized organozinc halides with p-toluenesulfonyl cyanide
作者:Ingo Klement、Klaus Lennick、Charles E Tucker、Paul Knochel
DOI:10.1016/s0040-4039(00)60640-8
日期:1993.9
Various alkyl, alkenyl, akynyl, benzylic, aromatic or heterocyclic organozinc halides bearing functional groups such as an ester, a boronic ester, a cyanide, a halide or a trialkoxysilyl group react under mild conditions with p-toluenesulfonyl cyanide affording polyfunctional nitriles in 69–93 % yields.
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.