The organocatalytic intramolecular aza-Michael reaction: a useful strategy to generate enantiomerically enriched nitrogen-containing heterocycles.

This review article provides a comprehensive update on the development of new methods for the asymmetric synthesis of α-(trifluoromethyl)-α-amino acids, covering the literature from 2006 to mid-February 2012. Most of the methods discussed are based on asymmetric additions across the carbon–nitrogen double bond of the imines derived from esters of 3,3,3-trifluoropyruvic acid. Medium to high levels of stereocontrol can be achieved using phenylglycinol-derived chiral auxiliaries attached to the nitrogen of the corresponding imines. Among the enantioselective approaches, impressive results were achieved through the application of the Strecker­ reaction using chiral thioureas, as well as chiral Brønsted acids, as organocatalysts. 1 Introduction 2 Stoichiometric Asymmetric Syntheses of α-(Trifluoromethyl)-α-amino Acids 3 Catalytic Asymmetric Syntheses of α-(Trifluoromethyl)-α-amino Acids 4 Miscellaneous 5 Conclusions

This review article surveys recent achievements in the preparation and biological properties evaluation of fluorinated aminophosphonates and aminophosphonic acids. Recently, in view of various important biological applications of the fluorinated aminophosphonic acid derivatives, the development of suitable synthetic methodologies for their preparation in racemic and in optically pure form has been a topic of great interest. Considerable progress has been made in asymmetric synthesis of fluorinated acyclic aminophosphonates and aminophosphonic acids using catalytic enantioselective reduction of fluorinated α-iminophosphonates, catalytic enantioselective addition of alkyl phosphites to fluorinated imines, and diastereoselective addition of alkyl phosphites to chiral fluorinated imines. A new efficient access to CF₃-substituted cyclic α-aminophosphonates has been developed based on metal-catalyzed carbene transfer reactions with diethyl 1-diazo-2,2,2-trifluoroethylphosphonate. New processes, e.g. enantioselective alkynylation and nucleophilic aromatic substitution involving fluorinated substrates are also considered.