Reactions of a Bis(vinyltrimethylsilane)nickel(0) N-Heterocyclic carbene complex with organic azides

The reactions of three-coordinate iron(0) and cobalt(0) alkene complexes (NHC)M(eta(2)-CH2CHSiMe3)(2) (NHC = N-heterocyclic carbene, M = Fe, Co) with organic azides proved an effective way for the preparation of iron and cobalt terminal imido complexes. The relevant reactions of nickel(0) alkene complex (NHC)Ni(eta(2)-CH2CHSiMe3)(2) with organic azides, however, have remained unexplored. Herein, we report the study on the reactions of [(IPr)Ni(eta(2)-CH2CHSiMe3)(2)] (IPr = 1,3-bis(2',6'-diisopropylphenyl)imidazole-2-ylidene) with organic azides. The interaction of [(IPr)Ni(eta(2)-CH2CHSiMe3)(2)] with 2,6-dimesitylphenyl azide (DmpN(3)) produced the two-coordinate imido complex [(IPr)Ni(NDmp)] (1) in a trace amount with the starting materials being largely remained. The reaction of [(IPr)Ni(eta(2)-CH2CHSiMe3)(2)] with 2,6-diisopropylphenyl azide (DippN(3)) gave IPrNNNDipp (2) as the only isolable product. The interaction of [(IPr) Ni(eta(2)-CH2CHSiMe3)(2)] with PhC(CF3)(2)N-3 produced an azanickelacyclobutane compound [(IPr)Ni(kappa-C,N-N(C(CF3)(2)Ph)CH(SiMe3)CH2)] (3) in high yield. The different products formed in these reactions reflect the influence of the steric and electronic nature of organic azides on reaction outcomes. Further study on the azanickelacyclobutane complex 3 indicated that it can convert into a new azanickelacyclobutane [(IPr)Ni(kappa-C,N-N(C(CF3)(2)Ph)CH2CHSiMe3)] (4). A nickel(II) amido alkyl complex [(IPr) Ni(NHC(CF3)(2)Ph)(CH2CHNC(CF3)(2)Ph)] (5) was also isolated from the decomposition reaction of 3. (C) 2020 Elsevier B.V. All rights reserved.