title: Highly enantioselective synthesis of alpha-alkyl-alanines via the catalytic phase-transfer alkylation of 2-naphthyl aldimine tert-butyl ester by using O(9)-allyl-N(1)-2',3',4'-trifluorobenzylhydrocinchonidinium bromide.
abstract: Systematic investigations to develop an efficient enantioselective synthetic method for alpha-alkyl-alanine by catalytic phase-transfer alkylation were performed. The alkylation of 2-naphthyl aldimine tert-butyl ester, 1E, with RbOH and O(9)-allyl-N-2',3',4'-trifluorobenzylhydrocinchonidinium bromide, 6, at -35 degrees C showed the highest enantioselectivities, up to 96% ee.
authors.affiliation: Research Institute of Pharmaceutical Science and College of Pharmacy, Seoul National University, Korea. ssjew@plaza.snu.ac.kr
authors.forename: Sang-sup
authors.initials: SS
authors.lastname: Jew
authors.forename: Byeong-Seon
authors.initials: BS
authors.lastname: Jeong
authors.forename: Jeong-Hee
authors.initials: JH
authors.lastname: Lee
authors.forename: Mi-Sook
authors.initials: MS
authors.lastname: Yoo
authors.forename: Yeon-Ju
authors.initials: YJ
authors.lastname: Lee
authors.forename: Boon-saeng
authors.initials: BS
authors.lastname: Park
authors.forename: Myoung Goo
authors.initials: MG
authors.lastname: Kim
authors.forename: Hyeung-geun
authors.initials: HG
authors.lastname: Park