Inorganic coordination polymers—XVII[1] the preparation and properties of tantalum(V) diphenylphosphinates

Abstract

Tantalum diphenylphosphinate alkoxides and oxides were prepared with one, two and three diphenylphosphinate groups per tantalum. They were found to be low molecular weight polymers in solution. The i.r. spectra of the tantalum diphenylphosphinate oxides indicate that the phosphinate groups have predominately one mode of coordination (probably symmetrical bridging) in Ta[OP(C 6H 5) 2O]O 2·H 2O, whereas in Ta[ OP( C 6 H 5) 2 O] O 3 2 · XH 2 O and Ta[ OP( C 6 H 5) 2 O] 3· XH 2 O they have a variety of coordination modes. The thermal stabilities of tantalum diphenylphosphinate dioxide and tantalum bis(diphenylphosphinate) sesquioxide were considerably greater than tantalum tris(diphenylphosphinate) oxide.