SYNTHESES AND RADICAL POLYMERIZATION BEHAVIOR OF NOVEL OPTICALLY-ACTIVE METHACRYLAMIDES HAVING (L)-LEUCINE STRUCTURE IN THE SIDE-CHAINS

Syntheses and radical polymerizations of methaerylamides having (L)leu cine and N-methyl-(L)-leucine methyl ester structures in the side chai ns N-methacryloyl-(L)-leucine methyl ester (MA-L-M) and N-methyl-N-met hacryloyl-(L)-leucine methyl ester (N-Me-MA-L-M) were carried out. The monomers were prepared by the reactions of methacryloyl chloride with the corresponding amino acid methyl esters. Radical polymerizations w ere carried out in the presence of appropriate initiators at 60 degree s C and 120 degrees C. MA-L-M afforded the corresponding polymer with M(n)s 38,000 similar to 372,000 in high yields, while N-Me-MA-L-M affo rded a trace amount of polymer at 60 degrees C and in a low yield even at 120 degrees C. Both inversion and increase of absolute value of sp ecific rotation were observed in the transformation from MA-L-M (+1.3 degrees C) to poly(MA-L-M) (-35.7 degrees C). Changes in the CD spectr al pattern and the conformation of the leucine moiety were confirmed f rom the monomer to polymer. (C) 1998 John Wiley & Sons, Inc.