Complexes of the two geometrical isomers of pyridine-2-carbaldehyde 2′-pyridylhydrazone with group vi metal carbonyls and substituted carbonyls

Abstract

Compounds of the types M(CO)₄L₂ and Mo(CO)₃L₂Y have been prepared where M = Cr, Mo, and W, L₂=Z-pyridine-2-aldehyde 2′-pyridylhydrazone and Y = PPh₃, AsPh₃, SbPh₃, Ph₃PSe and SO₂. The E-isomer of the hydrazone can be stabilised in the compounds Mo(CO)₄L₂, Mo(CO)₃L₂(PPh₃) and Mo(CO)₂L₂I₂. Some results of the halogen oxidations of Mo(CO)₄L₂ where L₂= either E- or Z-hydrazone are presented, compounds such as Mo(CO)₃(L₂)X₂, where L₂=Z-hydrazone and X = Br, I, and [L₂H₂]MoOX₅, where X = Cl, Br, having been isolated.