Abstract
The optically active and racemic forms of N-dodecyl and N-dodecyl-N-methylamino acids were synthesized by reductive N-alkylation of α-alanine and valine. The structures of these compounds were confirmed by NMR, IR and elementary analyses. N-dodecylamino acids are not soluble in water but N-dodecyl-N-methylamino acids are readily soluble. The L- and D-isomers of N-dodecyl N-methylamino acids were confirmed to be optically pure by HPLC using a chiral column. Surface tension and spectral change of a dye were used to determine the critical micelle concentration (cmc) of N-dodecyl-N-methylamino acids. The cmc values were the same, whether between optically active isomers or optical and racemic isomers. These phenomena suggest that the mechanism of micelle formation of N, N-dialkylated amino acids differs from that of N-acylamino acids.
