摘要:
eta(3)-alpha-Silabenzyl complexes Cp*M(CO)(2)-{eta(3)(Si,C,C)-Si(p-Tol)(3)} (M = Mo (1-Mo), W (1-W)) reacted with 2-substituted pyridines NC5H4(2-EHn) (E = O, S (n = 1); N (n = 2)) under mild conditions to give M-Si-E-C-N (E = O, N), W-Si-N-C-S, and M-E-C-N (E = S, N) metallacycles depending on the metal M or heteroatom E. These three kinds of metallacycles were characterized by spectroscopy, elemental analysis, and X-ray crystallography. The first two silametallacycles take on some silylene complex character and are considered to form via (aryl)silylene complex intermediates generated by cleavage of the Si-C(aryl) bond in the eta(3)-alpha-silabenzyl ligand of 1-Mo and 1-W.