Quantitative Construction of C≡C Bond: Renaissance of Reductive Coupling of Benzotribromides Promoted by Cu/Polyamine

Polymer Constructed Through the Formation of Carbon-Carbon Triple Bonds: Reductive Coupling Polymerization of Bis(benzylic gem-tribromide)s

Ethynylene-bridged polymers are currently synthesized by alkyne metathesis polymerization or Pd-catalyzed coupling between diethynylarene and dihaloarene. We report the formation of C≡C linkages in reductive coupling polymerization of bis(benzylic gem-tribromide)s promoted by Cu/polyamine under mild conditions. The polymer backbone was constructed through cascade formation of (Br)C═C(Br) bonds and C≡C bonds. This protocol provides a new method for synthesis of ethynylene-bridged polymers using monomers without alkynyl groups.