PREPARATION OF MOLYBDENUM(II) ETA-2-VINYL COMPLEXES VIA SEQUENTIAL C-CL ACTIVATION AND ALKYNE INSERTION

Reaction of the Schiff base ligand 1, prepared by the condensation of 2-chlorobenzaldehyde and N,N-dimethylethylenediamine with (eta(6)-C6H5 CH3)Mo(CO)(3) 2 resulted in the formation of the seven-coordinate moly bdenum(II) metallacycle, 3, by oxidative addition of the strong aromat ic C-Cl bond at molybdenum(0). The metallacycle 3 undergoes migratory insertion with electron-deficient internal acetylenes to afford novel eta(2)-vinyl complexes 4, resulting in net replacement of a C-Cl bond by a C-C bond. Copyright (C) 1996 Elsevier Science Ltd