Efficient and general asymmetric syntheses of (R)-chroman-4-amine salts
摘要:
Starting from a variety of substituted chroman-4-ones, a highly enantioselective CBS reduction using in situ-generated B-H catalyst gave (S)-chroman-4-ols. Azide inversion and reduction gave crude (R)-chroman-4-amines, which could be purified without chromatography by isolation as the (R)-mandelic or D-tartaric acid salts with good yields and excellent ee. (C) 2010 Elsevier Ltd. All rights reserved.
Synthesis of new derivatives of copper complexes of Josiphos family ligands for applications in asymmetric catalysis
作者:R. Oost、J. Rong、A. J. Minnaard、S. R. Harutyunyan
DOI:10.1039/c4cy00180j
日期:——
A series of new copper complexes containing chiral ferrocenyl diphosphine ligands of the Josiphos family have been prepared. These complexes have been studied in the catalytic asymmetric 1,2-addition of Grignard reagents to enones and aromatic ketones. Variation of the electronic and steric properties of the ligand resulted in a positive effect in the regio- and enantioselectivity of Grignard reagents