A New Synthesis of Optically Active<i>trans</i>β-Amino Alcohols by Asymmetric Ring-opening of Symmetrical Oxiranes
作者:Hiroyuki Yamashita
DOI:10.1246/cl.1987.525
日期:1987.3.5
The asymmetric ring-opening of symmetrical oxiranes with aniline or trimethylsilyl azide is effectively catalyzed by zinc (2R,3R)-tartrate or cupric (2R,3R)-tartrate to give trans N-phenyl (β-amino alcohol or trans O-trimethylsilyl 2-azido alcohols in 17–52% ee. The latter azido products can be easily converted into optically active trans β-amino alcohols by two-step procedure.
对称环氧乙烷与苯胺或三甲基甲硅烷基叠氮化物的不对称开环在 (2R,3R)-酒石酸锌或 (2R,3R)-酒石酸铜有效催化下得到反式 N-苯基(β-氨基醇或反式 O-三甲基甲硅烷基) 2-叠氮醇的 ee 含量为 17-52%。后者的叠氮产物可以通过两步程序轻松转化为光学活性的反式 β-氨基醇。
Stereoselective synthesis of 1,2-amino alcohols by asymmetric borane reduction of α-oxoketoxime ethers
作者:Moriyasu Masui、Takayuki Shioiri
DOI:10.1016/s0040-4039(98)01019-3
日期:1998.7
Asymmetricreduction of α-oxoketoxime ethers with the reagents prepared in situ from trimethyl borate and chiral amino alcohols derived from either L-proline or α-pinene was investigated. Both cyclic and acyclic α-oxoketoxime ethers were reduced to afford the corresponding chiral 1,2-amino alcohols with high enantioselectivities.
2,3,5,6-tetramethylmorpholine. V. Mechanism study of cyclization of 3,3′-iminobis-2-butanols
作者:Sven Hernestam、Gillis Stenvall
DOI:10.1002/jhet.5570170230
日期:1980.3
The mechanism of cyclization of 3,3′-iminobis-2-butanols to 2,3,5,6-tetramethylmorpholines in sulfuric acid is studied. Contrary to our prior suggestions, the ring closure seems to be exclusively a normal S N 2-type substitution. The partial inversion before the cyclization is discussed.