title: Highly enantioselective phase-transfer catalytic alkylation in the preparation of non-natural alpha-amino acids via solid phase synthesis using aldimine linker.
abstract: A new Merrifield-resin-derived glycinimine tert-butyl ester (9) was prepared and applied to the enantioselective synthesis of non-natural alpha-amino acids. High enantioselectivities (86 to >99% ee) were accomplished by employing the aldimine linker under phase-transfer alkylation conditions, using 50% aqueous CsOH in toluene/chloroform (7:3) at 0 degrees C in the presence of N-(9-anthracenylmethyl)-O(9)-allylcinchonidium bromide (10 mol %).
authors.affiliation: Research Institute of Pharmaceutical Science and College of Pharmacy, Seoul National University, Seoul 151-742, Korea. hgpk@plaza.snu.ac.kr
authors.forename: Hyeung-geun
authors.initials: HG
authors.lastname: Park
authors.forename: Mi-Jeong
authors.initials: MJ
authors.lastname: Kim
authors.forename: Mi-Kyung
authors.initials: MK
authors.lastname: Park
authors.forename: Hyun-Ju
authors.initials: HJ
authors.lastname: Jung
authors.forename: Jihye
authors.initials: J
authors.lastname: Lee
authors.forename: Sea-hoon
authors.initials: SH
authors.lastname: Choi
authors.forename: Yeon-Ju
authors.initials: YJ
authors.lastname: Lee
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: Jin-Mo
authors.initials: JM
authors.lastname: Ku
authors.forename: Sang-sup
authors.initials: SS
authors.lastname: Jew
mesh_terms: D000478:Alkylation; D000596:Amino Acids / Q000138:chemical synthesis*; D002384:Catalysis; D003432:Cross-Linking Reagents / Q000737:chemistry*; D007097:Imines / Q000737:chemistry*; D008968:Molecular Conformation; D013237:Stereoisomerism
chemical_list: D000596:Amino Acids; D003432:Cross-Linking Reagents; D007097:Imines