View in EDS

New chiral morpholine-pyrrolidine ligands affecting asymmetric selectivity in copper catalyzed Henry reaction.

Saved in:
Bibliographic Details
Title: New chiral morpholine-pyrrolidine ligands affecting asymmetric selectivity in copper catalyzed Henry reaction.
Authors: Angamuthu, Venkatachalam1, Tai, Dar-Fu1 dftai@gms.ndhu.edu.tw
Source: Tetrahedron Letters: International Organ for the Rapid Publication of Preliminary Communications in Organic Chemistry. Feb2019, Vol. 60 Issue 9, p653-659. 7p.
Subjects: Enantioselective catalysis, Morpholine, Pyrrolidine synthesis, Stereochemistry, Phenylacetic acid
Abstract: Graphical abstract Highlights • New chiral amines having chiral morpholine and pyrrolidine moieties were prepared. • These chiral amines formed copper (II) complexes in situ to catalyze Henry reaction. • Asymmetric Henry reaction furnished corresponding β-nitro alcohol in good yields. • Coupling of aromatic aldehyde with nitromethane achieved good enantioselectivity. • The stereochemical preference can be explained via a proposed transition state. Abstract In this study, several chiral diamine (35, 36, 37 and 39), triamine (24 and 25), diaminol (38, 42 and 43) and triaminol ligands (29 and 30) having chiral morpholine and pyrrolidine moieties conjugated constitutes, were prepared from commercially available (S)-2-amino-2-phenylacetic acid and (S)-proline. These ligands were complexed with copper (II) salt in situ and applied to asymmetric Henry reaction. Asymmetric addition of various structurally divergent aldehydes and nitromethane in the presence of 5 mol% of chiral ligand with CuCl 2 furnished corresponding β-nitro alcohol in good yields (up to 55–79%) with good enantioselectivity (up to 89%). [ABSTRACT FROM AUTHOR]
Copyright of Tetrahedron Letters: International Organ for the Rapid Publication of Preliminary Communications in Organic Chemistry is the property of Pergamon Press - An Imprint of Elsevier Science and its content may not be copied or emailed to multiple sites without the copyright holder's express written permission. Additionally, content may not be used with any artificial intelligence tools or machine learning technologies. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
Database: Engineering Source
Description
Abstract:Graphical abstract Highlights • New chiral amines having chiral morpholine and pyrrolidine moieties were prepared. • These chiral amines formed copper (II) complexes in situ to catalyze Henry reaction. • Asymmetric Henry reaction furnished corresponding β-nitro alcohol in good yields. • Coupling of aromatic aldehyde with nitromethane achieved good enantioselectivity. • The stereochemical preference can be explained via a proposed transition state. Abstract In this study, several chiral diamine (35, 36, 37 and 39), triamine (24 and 25), diaminol (38, 42 and 43) and triaminol ligands (29 and 30) having chiral morpholine and pyrrolidine moieties conjugated constitutes, were prepared from commercially available (S)-2-amino-2-phenylacetic acid and (S)-proline. These ligands were complexed with copper (II) salt in situ and applied to asymmetric Henry reaction. Asymmetric addition of various structurally divergent aldehydes and nitromethane in the presence of 5 mol% of chiral ligand with CuCl 2 furnished corresponding β-nitro alcohol in good yields (up to 55–79%) with good enantioselectivity (up to 89%). [ABSTRACT FROM AUTHOR]
ISSN:00404039
DOI:10.1016/j.tetlet.2019.01.048