Small molecule and high polymeric phosphazenes containing oxypyridine side groups and their organometallic derivatives: Useful precursors for metal nanostructured materials

Abstract

The pyridine-containing copolymers {NP(O2C12H8)](x)[NP(OC5H4N)(2)](1-X)}(n), with X = 0.7 (3a) and X = 0.8 (3b), and their respective organometallic derivatives of approximate formula {[NP(O2C12H8)](x)[NP-(OC5H4N circle MLn)(2)](1-X)}(n) with MLn = CpFe(dppe), CpRu(PPh2)(2), (n(5)-CH3C5H4)Mn(CO)(2), and W(CO)(5) have been prepared and characterized. As models, the simple compounds N3P3(OC6H5)(5)OC5H4N circle W(CO)(5) (2) and HOC5H4N circle W(CO)(5) (1) have also been prepared and characterized. Pyrolysis of the organometallic polymers in air affords metallic nanostructured materials, which according to transmission electron microscopy (TEM), scanning electron microseopy (SEM), back-electron scattered imaging (BEI), energy-dispersive X-ray microanalysis, and micro-Raman data can be formulated as the coexistence of metal and metal oxide in the case of tungsten and as manganese phosphate salt in the case of manganese. A plausible formation mechanism is proposed, and the pyrolysis of the organometallic polyphosphazene polymer as a new and general method to obtain metallic nanostructured materials is discussed.