om800488x_si_001.pdf (660.24 kB)
An Unsaturated Nickel(0) NHC Catalyst: Facile Preparation and Structure of Ni(0)(NHC)2, Featuring a Reduction Process from Ni(II)(NHC)(acac)2
journal contribution
posted on 2008-11-24, 00:00 authored by Kouki Matsubara, Satoshi Miyazaki, Yuji Koga, Yoshinori Nibu, Takaaki Hashimura, Taisuke MatsumotoA facile synthetic route to Ni(0)(NHC)2 from stable Ni(II)(acac)2 was established without common but labile Ni(0) precursors. The intermediate is a divalent mono-NHC adduct of Ni(acac)2, Ni(NHC)(acac)2. Reduction of Ni(NHC)(acac)2 in both the presence and absence of an NHC ligand gave Ni(NHC)2 in ca. 90% and 40% conversions, respectively. Ni(NHC)2, especially with bis(2,6-diisopropylphenyl)imidazolin-2-ylidene, has strong Ni−C(carbene) bonds and remarkable anagostic Ni−H(methyl) interactions, stabilizing its 14e unsaturated structure.
