Silole monomers, synthesis

Siloles 39 and 40 have been prepared in this way by Tamao and coworkers54 in 64 and 40% yield, respectively, the 2,5-dithienylsilole 40 being a useful monomer unit for the synthesis of thiophene-silole copolymers (see Section IV.B). 

Experimentally, a few series of oligo(l,l-silole)s have been prepared as models of poly(l, 1 -silolejs and their structures and photophysical properties have been studied in detail59,61,62. We have prepared a series of oligo( 1,1 -silolejs 57 having 3,4-diphenyl-2,5-dimethylsilole as a monomer unit. The stoichiometrically controlled reduction of 1,1-dichlorosilole with sodium followed by treatment with 1-methyl-1-chlorosilole affords tersilole57a and quater-silole 57b, as shown in Scheme 1059. Kira and coworkers have reported the synthesis of... 

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