Precise architecture of 1:1 alternating copolymers between germylenes and p ‐benzoquinone derivatives: First clear‐ cut evidence of biradical mechanism in polymerization chemistry

Germylenes bearing a bulky amide substituent have been copolymerized with various p ‐benzoquinone derivatives without any added catalyst to give novel class of germanium‐containing polymers having a tetravalent germanium unit and a p ‐hydroquinone unit alternatingly in the main chain (“oxidation‐reduction alternating copolymerization”). The resulting copolymers have high molecular weight (Mw>5.5×10 4 ) and are soluble in common organic solvents. A novel biradical mechanism involving a germyl radical and a semiquinone radical is proposed on the basis of ESR analysis of the propagating polymer end as well as trapping experiments using a disulfide or TEMPO radical.