Cleavage of Carbon−Carbon Bonds in Alkyl Cyanides Using Nickel(0)

The reaction of the complex [(dippe)NiH] 2 ( 1 ) with a variety of alkyl cyanides afforded nickel(0) compounds of the type [(dippe)Ni(η 2 -RCN)], where R = Me, Et, Pr, i Pr, t Bu, cyclopropyl, cyclobutyl, adamantyl ( 2 − 9, respectively). When compounds 2 − 9 were warmed to yield oxidative addition products, the thermal reaction proceeded only in the case of 2 to produce [(dippe)Ni(Me)(CN)] ( 10 ). Photochemical activation did produce oxidative addition products from compounds 2 − 8, which rapidly evolved to the β-elimination products of the organic moiety in most cases and to the formation of [(dippe)Ni(CN) 2 ] ( 11 ). Reaction of 1 with acetonitrile in the presence of BPh 3 gives [(dippe)Ni(η 2 -MeCNBPh 3 )] ( 12 ), which does not undergo thermal C−CN cleavage upon heating. X-ray crystal structures are reported for 10 − 12 .