Synthesis and use of trans-dichlorido-tetrakis-(N-R-imidazole)nickel(II) complexes in Kumada-Tamao-Corriu cross-coupling reactions

Two dichlorido-tetrakis-(N-R-imidazole)nickel(II) complexes (R = 2,6-diisopropylphenyl (1): methyl (2)) have been synthesised. A single crystal X-ray diffraction study was carried out for 1, which revealed a centrosymmetric complex with the nickel centre placed in an octahedral coordination environment. Both complexes showed high activities (TOFs up to 60200 mol(ArBr) mol(Ni)(-1) h(-1)) in Kumada-Tamao-Corriu cross-coupling of arylhalides with arylgrignards. No significant differences in activity were observed between the two complexes. (C) 2011 Elsevier Ltd. All rights reserved.