论文部分内容阅读
A series of C_2-symmetric and asymmetric chiral thiourea derivatives were synthesized from commercial L-phenylalanine.All of the new compounds have been fully characterized by IR,~1H NMR,~(13)C NMR,MS spectra and elemental analyses.The chiral thioureas were used as chiral ligands in the catalytic enantioselective ethylation of aldehydes with diethylzinc,the corresponding sec-alcohols were gained with excellent enantioselectivities(up to 87.1%ee) and high yields(up to 76.7%) after the conditions were optimized.
A series of C_2-symmetric and asymmetric chiral thiourea derivatives were synthesized from commercial L-phenylalanine. All of the new compounds have been fully characterized by IR, ~ 1H NMR, ~ (13) C NMR, MS spectra and elemental analyzes. The chiral thioureas were used as chiral ligands in the catalytic enantioselective ethylation of aldehydes with diethylzinc, the corresponding sec-alcohols were gained with excellent enantioselectivities (up to 87.1% ee) and high yields (up to 76.7%) after the conditions were optimized.