Yuning Li, Y. Kawakami
Jan 7, 1999
Citations
0
Influential Citations
27
Citations
Journal
Macromolecules
Abstract
An optically active (>98.2% ee) five-membered cyclic silicon compound, (S)-2-(1-naphthyl)-2-phenyl-5,5-dimethyl-1-oxa-2,5-disilacyclopentane, was synthesized by intramolecular hydrosilylation of (1S)-1-(1-naphthyl)-1-phenyl-1-vinyl-3,3-dimethyl-3-hydro-1,3-disiloxane in good yield (as high as 74.3%). This cyclic compound could be easily polymerized by common nucleophilic initiators, such as PhLi, MeONa, and t-BuOK. The polymerization using the lithium initiator showed a very high regioselectivity in ring opening (head-to-tail content 98.7% at 0 °C) and consequently afforded an optically active and highly isotactic poly[{(1S)-1-(1-naphthyl)-1-phenyl-3,3-dimethyldisiloxane-1,3-diyl}ethylene] ([α]25D = − 8.5°, Mn = 20 800 (calculated from 29Si NMR), Mw/Mn = 1.12 (by SEC)).