摘要:
Treatment of cyclic diaminocarbene complexes (CO)(5)M=CNH(CH2)(m)NH (1) (M=Cr, Mo, W; m = 2, 3) with acylating agents resulted in the formation of the corresponding isocyanide complexes (CO)(5)MCN(CH2)(m)NH2-m(COR)(n) (M=Cr, Mo, W; m = 2, 3; n = 1, 2; R=PhCH3) in high yields. It appears that the N-acyl group destabilizes the diaminocarbene complexes and causes the cleavage of the C-N bond to form the isocyanide product. The reaction pathway leading to the isocyanide complexes is discussed. The crystal structure of(CO)(5)WC=N(CH2)(2)N(COPh)(2) has been determined.