Enantioselective Synthesis of <i>N</i>-Benzylic Heterocycles: A Nickel and Photoredox Dual Catalysis Approach
作者:Cristofer Pezzetta、Davide Bonifazi、Robert W. M. Davidson
DOI:10.1021/acs.orglett.9b03338
日期:2019.11.15
Reported herein is a dual nickel- and photoredox-catalyzed modular approach for the preparation of enantioenriched N-benzylic heterocycles. α-Heterocyclic carboxylic acids, easily obtainable from common commercial material, are reported as suitable substrates for a decarboxylative strategy in conjunction with a chiral pyridine–oxazoline (PyOx) ligand, providing quick access to enantioenriched drug-like
METHOD FOR PRODUCING OPTICALLY ACTIVE CARBOXYLIC ACID ESTER
申请人:TOKYO UNIVERSITY OF SCIENCE FOUNDATION
公开号:US20170008820A1
公开(公告)日:2017-01-12
Provided is a method for producing an optically active carboxylic acid ester at a high yield and with high enantioselectivity using dynamic kinetic resolution, said optically active carboxylic acid ester having an α-nitrogen substituent. This method for producing an optically active carboxylic acid ester includes a step in which racemic carboxylic acid represented by formula (a) and a specific alcohol or phenol derivative are reacted in a polar solvent having a dipole moment of at least 3.5 in the presence of an acid anhydride and an asymmetric catalyst, one enantiomer of the racemic carboxylic acid is selectively esterified, and the other enantiomer is racemized. In formula (a), Ra1 represents a nitrogen-containing heteroaromatic ring group bonded to an assymetric carbon via a nitrogen atom constituting a ring, and Ra2 is an organic group.
application of microwave in organic synthesis, sparked by the pioneering papers of Gedye, Majetich and their co-workers in 1986: has demonstrated that reactions can be conducted safely in commercial microwave ovens with remarkable rate enhancements and dramatic reductions of reaction times compared to conventional heating.5 Bogdal et ul. reported a method of N-alkylations of carbazole undermicrowave irradiation
Lactam polymers has been modified with sodium borohydride (NaBH
4
) to yield lactam polymers bearing hydroxyl functional groups. These functional groups are useful for the covalent attachment of reactive groups, fluorescent probes, antimicrobial agents, bioactive factors, and drugs. The resulting as components for medical devices, specifically ophthalmic devices and more specifically contact lenses. Hydrogels based on these polymers are also useful for biomedical applications in the areas of drug delivery, tissue engineering, and implantable devices.