Unsaturated polymers containing boron and thiophene units in the backbone

Abstract

2,5-Dialkynylthiophenes (RC[triple bond, length half m-dash]C)₂C₄H₂S (R = Ph, Me₃Si or Bu^t) treated successively with HBCl₂ and Et₃SiH in CH₂Cl₂ undergo hydroboration polymerization to give intensely-coloured polymers of general structure –[CH[double bond, length half m-dash]CR–BCl–CR[double bond, length half m-dash]CH–C₄H₂S]_n– for which the ¹¹B NMR resonances occur ca. 50 ppm upfield of those for analogous monomers.

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