title: Synthesis and catalytic activity of iron complexes with bidentate NHC ligands.
abstract: A family of well-defined Fe(II) complexes of the type {BnN(N-CH2(CH2)n-N'-tert-butyl-imidazole-2-ylidene)2}FeCl2 (Bn = benzyl; n = 1 (1) or 2 (2)), {BnN(N-CH2(CH2)n-N'-methylbenzimidazole-2-ylidene)2}FeCl2 (n = 1 (3) or 2 (4)) and {BnN(N-CH2CH2CH2-N'-methylbenzimidazole-2-ylidene)2}FeBr2 (5) has been synthesized. These complexes are rare examples of Fe species supported by bidentate NHC ligands. Complexes 2, 3, 4 and 5 were characterized by X-ray crystallography and in all cases a distorted tetrahedral geometry is observed around the Fe center. The magnetic data is consistent with the complexes containing non interacting high spin Fe(II) centers (S = 2) and indicates that a large zero-field splitting (D) is present. The new complexes are highly active pre-catalysts for the homo-coupling of Grignard reagents.
authors: The Department of Chemistry, Yale University, P. O. Box 208107, New Haven, Connecticut 06520, USA.
authors: Jianguo
authors: J
authors: Wu
authors: Wei
authors: W
authors: Dai
authors: Joy H
authors: JH
authors: Farnaby
authors: Nilay
authors: N
authors: Hazari
authors: Jennifer J
authors: JJ
authors: Le Roy
authors: Valeriu
authors: V
authors: Mereacre
authors: Muralee
authors: M
authors: Murugesu
authors: Annie K
authors: AK
authors: Powell
authors: Michael K
authors: MK
authors: Takase