An efficient enantioselective α-amination of 2-substituted 3-indolinones has been achieved for the first time using hydroquinidine as a chiral catalyst through an aza-Michael reaction. The desired α-hydrazino esters are obtained in excellent yields with high enantiomeric excess leading to a quaternary stereocenter with a broad substrate scope.
A stereoselective total synthesis of phomonol, following organocatalytic enantioselective epoxidation and intramolecular oxa‐Michael reaction as key steps, is described. The use of readily available D‐tartaric acid as a chiral source renders this approach quite simple and attractive.
:
Synthesis of isoxazole structural heterocyclic compounds is important due to their wide range of biological activities. In the present article, we report a convenient and easy method for the synthesis of 4-arylmethylidene-3-substituted-isoxazol-5(4H)-ones by the one-pot three-component reaction of aldehydes, β-keto ester, and hydroxylamine hydrochloride cat-alyzed by sulfated tin oxide as a heterogeneous catalyst.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.