Product Selectivity of Esterification of L-Aspartic Acid and L-Glutamic Acid Using Chlorotrimethylsilane.

TMSCI works as an acid catalyst precursor for selective esterification of L-aspartic and L-glutamic acids in the presence of primary, secondary and tertiary alcohols. Although excess TMSCI was required for the completion of esterification, the resulting alkyl TMS ether could be azeotropically removed by simple evaporation with alcohol.