使用衍生自稳定的螺硼酸酯,通过硼烷介导的单一异构体 ( E )- 和 ( Z ) -O-苄基肟醚的还原,合成了高对映体纯的 (1-芳基)-和 (1-萘基)-1-乙胺( S )-二苯基缬氨醇和乙二醇作为手性催化剂。伯 ( R )-芳基乙胺是通过使用 15% 的催化剂将纯 ( Z )-乙酮肟醚还原至 99% ee来制备的。描述了使用对映纯(1-萘-1-基)乙胺作为手性前体合成新的和已知的拟钙剂类似物的两种方便且容易的方法。
使用衍生自稳定的螺硼酸酯,通过硼烷介导的单一异构体 ( E )- 和 ( Z ) -O-苄基肟醚的还原,合成了高对映体纯的 (1-芳基)-和 (1-萘基)-1-乙胺( S )-二苯基缬氨醇和乙二醇作为手性催化剂。伯 ( R )-芳基乙胺是通过使用 15% 的催化剂将纯 ( Z )-乙酮肟醚还原至 99% ee来制备的。描述了使用对映纯(1-萘-1-基)乙胺作为手性前体合成新的和已知的拟钙剂类似物的两种方便且容易的方法。
Asymmetric synthesis using chirally modified borohydrides. Part 3. Enantioselective reduction of ketones and oxime ethers with reagents prepared from borane and chiral amino alcohols
The asymmetric reduction of aromatic and aliphatic ketones, halogeno ketones, hydroxy ketones, keto esters, and ketone oxime ethers with reagents prepared from borane and chiral amino alcohols has been investigated. When α,α-diphenyl β-amino alcohols, such as (2S,3R)-(–)-2-amino-3-methyl-1,1 -diphenylpentanol (2d), were used as a chiral auxiliary, very high enantioselectivities (ca. 90 % e.e.) were
The remarkable effect of E/Z isomers on the catalytic asymmetric hydrogenation of oximes
作者:Albert S. C. Chan、Chih-Chiang Chen、Ching-Wen Lin、Ying-Chih Lin、Ming-Chu Cheng、Shie-Ming Peng
DOI:10.1039/c39950001767
日期:——
The E and Z isomers of 1-acetonaphthone oxime are isolated, characterized, and subjected to catalyticasymmetrichydrogenation; the chiral products from the asymmetrichydrogenation reflect the effect of the E and Z isomers on the enantioselectivity of the reaction.