Nickel catalysts polythiophenes

Quite early, Grignard compounds were coupled with organohalogen compounds by using nickel complexes as catalysts. In 1978 Yamamoto et al. prepared poly(/7-phenylene) from 1,4-dibromobenzene (Fig. 8b). Two years later the same authors reported the preparation of polythiophene using the same procedure but starting from 2,5-dibromothiophene. 

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