Reaction of E,1,4-poly(2-triethylsilyl-1,3-butadiene) with Bromine. Stereoselective Synthesis of Z-1,4-poly(2-bromo-1,3-butadiene)

摘要

There is considerable interest in chemical modification of intact polymers (1-3). Regio- and stereoselective electrophilic substitution reaction with loss of the silyl group is a characteristic reaction of monomeric vinyl silanes (4). While protodesilation of poly (trimethylsilylacetylene) to yield poly (acetylene) has been reported (5-7), reactions of polymeric vinyl silane systems with halogens are unexplored. Addition of bromine to E-1,4-poly(2-triethylsilyl-1,3-butadiene) (I) followed by treatment with potassium fluoride dihydrate yields Z-1,4-poly-(2-bromo-1,3-butadiene) (II). The mechanism of this reaction is discussed. The product polymer has been characterized by 1H, 13C NMR, IR, GPC, TGA and elemental analysis. Butadienes, reprints. (MJM)