Lanthanide triflates are stable in water. It is possible for lanthanides to undergo many organic reactions in environmentally friendly solvents. This makes lanthanides very promising in the field of green chemistry. This review describes the recent development of the lanthanide-catalyzed organic reactions in protic solvents. Those reac-tions include Diels-Alder, Aldol, Allylation, acetalization, pericyclization, radical reactions as well as some newly-developed lanthnides-based catalysts.
LUO SanzhongZHANG BaolianXIAN MingAdam JanczukXIE WenhuaCHENG JinpeiPeng George Wang
Since the discovery of its roles as a good small-organic-molecule catalyst in intramolecular aldol reactions, pro line has drawn considerable attention in synthetic chemistry due to its similarity to the type-Ⅰ aldolases. Recently,List and others have reported some new direct asymmetric intermolecular reactions catalyzed by proline, including aldol, Mannich, Michael, and other analogous reactions. Except for two recent examples, [1,2] proline catalyzed aldol reactions in aqueous micelles have not been reported, nor have other amino acids as organocatalysts in directly catalyzing aldol reaction been reported. Herein we wish to present our recent results regarding environmentally be nign direct aldol reactions catalyzed by amino acids including proline, histidine and arginine in aqueous media.……
PENG Yi-Yuan WANG Qi DING Qiu-Ping HE Jia-Qi CHENG Jin-Pei