162586-55-2Relevant academic research and scientific papers
Multiple-imido complexes of molybdenum: Synthesis and reactivity of the d0 Mo(=NR)3 functional group
Morrison, Donald L.,Wigley, David E.
, p. 2610 - 2616 (2008/10/08)
Red-orange crystals of the tris(imido) anion of molybdenum, [Mo(NAr)3Cl]- (3, Ar = 2,6-C6H3-i-Pr2) are isolated as the [Li(THF)4]+ salt from the rapid workup of the reaction between Mo(NAr)2Cl2(THF)2 (1) and 2 equiv of LiNHAr (in THF). [Li(THF)4][Mo(NAr)3Cl] (3) constitutes the kinetic product of this reaction since it readily reacts with byproduct H2NAr to afford stable Mo(NAr)2(NHAr)2 (4). Complex 3 undergoes nucleophilic attack by PMe3, MeLi, Me3CCH2Li, or Br- to form Mo(NAr)3(PMe3) (5), [Li(THF)4][Mo(NAr)3Me] (6), [Li(THF)4][Mo(NAr)3(CH2CMe3)] (7), and [n-Bu4N][Mo(NAr)3Br] (8), respectively. The imido ligands in these tris(imido) complexes are also subject to electrophilic attack by a range of electrophiles to afford four- or five-coordinate bis(imido) complexes of Mo(VI). Thus, Mo(NAr)2(OCMe3)2 (9) is prepared from Mo(NAr)3(PMe3) (5) and Me3COH, while metallacyclic Mo[NArC(O)NPh](NAr)2(PMe3) (10) arises from Mo(NAr)3(PMe3) (5) and PhNCO. [Li(THF)4][Mo(NAr)3Cl] (3) is readily protonated by cyclopentadiene C5H6 to provide CpMo(NAr)2(NHAr) (11, Cp = [η5-C5H5]-). The reaction of [HNMe3]BPh4 with [Li(THF)4][Mo(NAr)3(CH2CMe3)] (7) protonates an imido ligand rather than the alkyl to give Mo(NAr)2(NHAr)(CH2CMe3) (12). The electronic structure of the d0 Mo(=NR)3 functional group is described in terms of related M(σ+2π)3 complexes with 3-fold symmetry.
