Synthesis and crystal structures of cyclodiazastannoxides fused cyclopentadienyl M–Sn (M = Mo, W) bonded organometallic heterocycle

The condensation reaction of CH3COC5H4M(CO)3SnCl3 (M = Mo or W) with PyCONHNH2 (Py = 2,3,4-pyridyl or 2-pyridylmethyl) in mild conditions yields cyclodiazastannoxides fused cyclopentadienyl M–Sn bonded organometallic heterocycle {μ-[C5H4(CH3)Cdouble bond; length as m-dashN–Ndouble bond; length as m-dashC(O)PyH]M(CO)3SnCl3}. The similar reaction of CH3COC5H4M(CO)3SnCl3 with ArCONHNH2 (Ar = 2-furanyl) gives complexes μ-[C5H4(CH3)Cdouble bond; length as m-dashN–Ndouble bond; length as m-dashC(O)Ar]M(CO)3SnCl2(H2O), in which the water molecule can be replaced by other N-donor ligands, such as pyridine or 4,4-bipyridine. Arene-bridged organometallic heterocyclic complexes μ-{[C5H4(CH3)Cdouble bond; length as m-dashN–Ndouble bond; length as m-dashC(O)]2C6H4}{M(CO)3SnCl2(Solvent)}2 have also been prepared by the reaction of CH3COC5H4M(CO)3SnCl3 with terephthaloyl hydrazine. In these new organometallic heterocyclic complexes, it seems that the tin atom prefers to be six-coordinate through absorbing the chloridion or solvent molecules.