Synthesis and polymerization of chiral acrylamidosulfonic acids

Reductive amination of (1S)-(+)-10-camphorsulfonic acid with NaCNBH3/NH4OAc has afforded diastereomeric exo- and endo-aminosulfonic acids, that can be separated by crystallization from methanol. Treatment of these diastereome rs with acryloyl chloride gave high yields of novel, chiral acrylamides tha t incorporate both a sulfonic acid substituent and a chiral auxiliary. The free radical (AIBN) polymerization of these acrylamides gave high yields (8 4-90%) of novel, water-soluble polyacrylamides (M-w = 5500-7800). H-1 NMR s tudies showed these to be essentially atactic. Their circular dichroism spe ctra were similar to their corresponding acrylamide monomers. This indicate s that the sulfonic acid chiral auxiliary in the monomer precursors does no t induce and/or maintain macroasymmetry in the resulting polyacrylamide cha ins. Hydrogels with equilibrium water contents as high as 99.96% could be o btained by copolymerizing {(NH4)(2)S2O8 initiator) these chiral acrylamides with equimolar acrylamide and varying ratios of N,N'-methylenebisacrylamid e as cross-linker.