Oxazaborolidine-mediated asymmetric reduction of 1,2-diaryl-2-benzyloxyiminoethanones and 1,2-diarylethanediones
摘要:
Highly enantioselective reduction of 1,2-diaryl-2-benzyloxyiminoethanones and 1,2-diarylethanediones was conducted using oxazaborolidine derived from L-threonine and borane complexes to give B-imino alcohols and 1,2-diaryl-1,2-ethanediols in high enantiomeric purity. Subsequent reduction of the imino functionality of the former products afforded either syn- or anti-2-amino-1,2-diarylethanols in high enantiomeric purity by choosing appropriate reduction methods. (C) 1998 Elsevier Science Ltd. All rights reserved.
Preparation of Optically Pure (1R, 2S)- and (1S, 2R)-DI-<i>p</i>-Methoxyphenyl Amino Alcohol
作者:Jian Liao、Yili Zhang、Zhi Li、Daimo Chen、Albert S. C. Chan
DOI:10.1080/00397910008086985
日期:2000.9
Abstract Racemic di-p-methoxyphenyl amino alcohol was synthesized in three steps. Optically pure di-p-methoxyphenyl amino alcohols were obtained by recrystallization. The absolute configuration of the amino alcohol was determined by X-ray crystallography.
摘要 分三步合成了外消旋二对甲氧基苯基氨基醇。通过重结晶获得光学纯的二对甲氧基苯基氨基醇。氨基醇的绝对构型通过 X 射线晶体学确定。
Stereodivergent approach to syn- and anti-2-amino-1,2-diarylethanols using oxazaborolidine-mediated asymmetric reduction
Highly enantioselective reduction of 1,2-diaryl-2-benzyloxyiminoethanones was conducted using oxazaborolidine derived from L-threonine and BH3. SMe2 to give B-imino alcohols in high enantiomeric purity. Subsequent reduction of the imino functionality afforded either syn- or anti-2-amino-1,2-diarylethanols in high enantiomeric purity by choosing appropriate reduction conditions. (C) 1997 Elsevier Science Ltd.
Oxazaborolidine-mediated asymmetric reduction of 1,2-diaryl-2-benzyloxyiminoethanones and 1,2-diarylethanediones
Highly enantioselective reduction of 1,2-diaryl-2-benzyloxyiminoethanones and 1,2-diarylethanediones was conducted using oxazaborolidine derived from L-threonine and borane complexes to give B-imino alcohols and 1,2-diaryl-1,2-ethanediols in high enantiomeric purity. Subsequent reduction of the imino functionality of the former products afforded either syn- or anti-2-amino-1,2-diarylethanols in high enantiomeric purity by choosing appropriate reduction methods. (C) 1998 Elsevier Science Ltd. All rights reserved.
Total Synthesis of Lyconesidine B: Approach to a Three-Dimensional Tetracyclic Skeleton of Amine-Type Fawcettimine Core and Studies of Asymmetric Synthesis
for its synthesis. As a result, we established a synthetic route to the CD ring decahydroquinoline via cyclopropanation followed by ring-opening and reduction, and the AB ring tetracyclic core by ene-yne metathesis. In the ene-yne metathesis, the use of a quaternary ammonium salt solved the issues of the conformation of the substrate as well as the deactivation of the catalyst. The first total synthesis
Lyconesidine B,从石松中分离出来,其特征在于氧化胺型核心,反式-稠合的 CD 环在轴向位置上有一个羟甲基。因为这种生物碱的 C13 的氧化水平不同于其他 fawcettimine 型生物碱,我们研究了一种合适的合成策略。因此,我们建立了一条通过环丙烷化然后开环和还原生成CD环十氢喹啉的合成路线,以及通过烯-炔复分解生成AB环四环核的路线。在烯-炔复分解中,季铵盐的使用解决了底物构象以及催化剂失活的问题。第一次全合成是通过四环骨架的立体选择性衍生化实现的。此外,我们研究了不对称环丙烷化,