SYNTHESES AND RADICAL POLYMERIZATIONS OF NOVEL OPTICALLY-ACTIVE VINYLAND ISOPROPENYL CARBAMATES HAVING L-LEUCINE STRUCTURES

Syntheses and radical polymerizations of vinyl and isopropenyl carbama tes having L-leucine methyl ester structures, N-vinyloxycarbonyl-L-leu cine methyl ester (VOC-L-M) and N-isopropenyloxycarbonyl-L-leucine met hyl ester (IOC-L-M), were carried out. VOC-L-M and IOC-L-M were prepar ed by the reactions of L-leucine methyl ester with vinyl and isopropen yl chloroformates in the presence of sodium hydrogen carbonate. The ra dical polymerization of VOC-L-M with AIBN (1 mol %) in bulk, chloroben zene, methanol, and N,N-dimethylformamide afforded the corresponding p olymer (poly(VOC-L-M)) with (M) over bar(n) 7,400-19,000. Meanwhile, I OC-L-M afforded no polymer with AIBN at 60 degrees C but afforded a po lymer having low molecular weight with BPO at 80 degrees C, The glass transition temperatures of poly(VOC-L-M) and poly(IOC-L-M) were 53 and 65 degrees C, respectively. The 10% weight loss temperatures of poly( VOC-L-M) and poly(IOC-L-M) under nitrogen were 255 and 173, respective ly. The copolymerization parameters of VOC-L-M (M(1)) and vinyl acetat e (M(2)) were evaluated as r(1) = 0.92 and r(2) = 0.63. (C) 1996 John Wiley & Sons, Inc.