Stereoregularity in Ziegler-Natta and Anionic Polymerization of 2-((Trimethylsilyl)methyl)-1,3-Butadiene. Protodesilation of cis-1,4-Poly(2-((trimethylsilyl)methyl)-1,3-butadiene)

摘要

Ziegler-Natta polymerization of 2-(TRIMETHYLSILYL)METHYL-1,3 -butadiene (I) catalyzed by triethylaluminum and titanium tetrachloride yields a polymer whose microstructure, as established by 1H, 13C, and 29Si NMR spectroscopy, is predominantly comprised of cis-1,4 units. On the other hand, anionic polymerization of I yields a polymer whose microstructure is made up of cis-1,4-, trans-1,4-, and 3,4-units. Protodesilation of cis-1,4-poly2-(trimethylsilyl)-methyl-1,3-butadiene with iodine in D2O yields poly(3-deuterio-2-methylene-butane). The mechanism of this reaction is discussed. Stereoregular, Polymerization, Butadienes, Silanes, Methylradicals, Reprints. (mjm)