名称:
Synthesis and redox properties of the cycloheptatrienylmolybdenum complexes [MoX(N–N)(η-C7H7)]z+, (N–N=2,2′-bipyridine or 1,4-But2-1,3-diazabutadiene; z=0, X=Br or Me; z=1, X=NCMe, CNBut or CO)
摘要:
The complexes [MoBr(N-N)(eta-C7H7)] (N-N = 2,2'-bipyridine (bipy), 1a; N-N = 1,4-Bu-2(t)-1,3-diazabutadiene (Bu-t-dab), (1b) have been prepared by reaction of [MoBr(CO)(2)(eta-C7H7)] with N-N in refluxing toluene. Treatment of 1a or 1b with MeLi affords [MoMe(N-N)(eta-C7H7)] (N-N = bipy or Bu-t-dab). The acetonitrile complexes [Mo(NCMe)(N-N)(eta-C7H7)][PF6], generated by reaction of [Mo(eta-C6H5Me)(eta-C7H7)][PF6] with N-N in NCMe, are precursors to [MoX(N-N)(eta-C7H7)][PF6] X = CNBut or CO; N-N = bipy or Bu-t-dab), through substitution of NCMe by X. Cyclic voltammetric studies reveal that each of the complexes [MoX(N-N)(eta-C7H7)](z+) (X = Me, Br, NCMe or CNBut; N-N = bipy or Bu-t-dab) exhibits a reversible one-electron oxidation and the 17-electron radicals derived from 1a, b and [Mo(CNBut)bipy)(eta-C7H7][PF6] have been isolated. E degrees values for the complexes [MoX(N-N)(eta-C7H7)](z+), demonstrate that in each case the bipy derivative is more easily oxidised than the corresponding Bu-t-dab analogue. (C) 1998 Elsevier Science S.A. All rights reserved.