Lewis-Acid-Mediated Stereospecific Radical Polymerization of Acrylimides Bearing Chiral Oxazolidinones.
Lewis acid (MgBr2)-catalyzed radical polymerization of acrylimides bearing chiral oxazolidinones gave highly isotactic polyacrylimides with up to >99% meso tetrad (mmm) selectivity. Polymerization in the absence of Lewis acid gave atactic polymers with 80% racemo diad (r) selectivity; the selectivity was deliberately tuned from 80% r to >99% mmm by varying the polymerization conditions. The polyacrylimide was quantitatively converted to corresponding polyacrylates while preserving the stereoregularity, thus providing a general method for the synthesis of atactic to isotactic polyacrylates.
Institute for Chemical research, Kyoto University, Kyoto 611-0011 (Japan).
Takehiro
T
Fujita
Institute for Chemical research, Kyoto University, Kyoto 611-0011 (Japan). yamago@scl.kyoto-u.ac.jp.
Shigeru
S
Yamago
Lewis acid; chiral auxiliary; radical polymerization; stereoselective reaction; stereospecific polymerization