title: Cinchonium Betaines as Efficient Catalysts for Asymmetric Proton Transfer Catalysis: The Development of a Practical Enantioselective Isomerization of Trifluoromethyl Imines.
abstract: We have developed a new class of cinchonium betaine catalysts bearing both a base moiety and an aromatic moiety as an N-substituent of the quinuclidine motif. These cinchonium betaines were found to promote proton transfer catalysis with 1000-5000 turnovers per 24 h, thereby enabling us to realize highly efficient enantioselective isomerization of trifluoromethyl imines to provide a practical access to optically active trifluoromethylated amines.
authors: Department of Chemistry, Brandeis University , Waltham, Massachusetts 02454-9110, United States.
authors: Xiao
authors: X
authors: Zhou
authors: Department of Chemistry, Brandeis University , Waltham, Massachusetts 02454-9110, United States.
authors: Yongwei
authors: Y
authors: Wu
authors: Department of Chemistry, Brandeis University , Waltham, Massachusetts 02454-9110, United States.
authors: Li
authors: L
authors: Deng
mesh_terms: D001622:Betaine / Q000031:analogs & derivatives*; D002384:Catalysis; D005466:Fluorocarbons / Q000737:chemistry*; D007097:Imines / Q000737:chemistry*; D015394:Molecular Structure; D011522:Protons
chemical_list: D005466:Fluorocarbons; D007097:Imines; D011522:Protons; D001622:Betaine