Oxidation-reduction alternating copolymerization of germylene and N-phenyl-p-quinoneimine

The germylenes bis[bis(trimethylsilyl)amido]germanium (1a) and bis[t-butyl-trimethylsilyl]amido]germanium (1b) were reacted with N-phenyl-p-quinoneimine (2) to give copolymers (3a and 3b) with alternating tetravalent germanium and p-aminophenol units. The copolymerization took place smoothly at 0°C without added catalyst or initiator. 1 acted as a reductant monomer, and 2 acted as an oxidant monomer (oxidation-reduction alternating copolymerization). Product copolymers were obtained in very high yields and had high molecular weights. The copolymers were soluble in toluene, benzene, n-hexane and chloroform, whereas they were insoluble in acetonitrile and acetone. Additionally, they were stable toward hydrolytic degradation. Electron spin resonance (ESR) spectroscopic studies of the reaction suggested a structure of a stable germyl radical and a plausible mechanism of biradical copolymerization.