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The combined regio- and stereoselective carbometalation of cyclopropenyl amides, followed by the addition of an acyl silane, led to the formation of polysubstituted cyclopropyl derivatives as unique diastereoisomers. Upon warming of the reaction mixture to room temperature, a Brook rearrangement proceeded with inversion of configuration to provide ready access to δ-ketoamides possessing a quaternary carbon center with high enantiomeric ratios through selective C-C bond cleavage of the ring.

A highly regioselective cycloaddition procedure of electron-deficient allenes with trifluorodiazoethane is developed.

This work describes the design, synthesis, and application of de novo chiral fluorinating agents as analogues of popular N-fluorodibenzenesulfonimide (NFSI). The fluorination step by means of elemental fluorine is presented. Enantioselective fluorination is demonstrated in cyclic β-keto esters and in the synthesis of BMS-204352 (up to 86 % ee). Oxidative aminofluorination is also examined.

The enantioselective Strecker reaction of ketimines (I) with trimethylsilyl cyanide is used for the preparation of quinazolinones (III).

A novel enantioselective diynylation of cyclic N-acyl trifluoromethylketimines with chloramphenicol-amine derivatives as chiral additives has been successfully developed. A series of diynylated tertiary trifluoromethylcarbinamines were obtained in high yields with good to excellent enantioselectivities (with up to 99% ee).

An efficient, catalytic, and enantioselective 1,2-addition of terminal 1,3-diynes to aromatic ketones was realized in the presence of 10 mol% of a Cu(OTf)2-hydroxycamphor-sulfonamide complex, affording chiral tertiary alcohols in up to 94% yield and 90% ee.

In the presence of saccharide-derived bifunctional amine-thiourea catalysts, the direct aldol condensation of trifluoroacetaldehyde methyl hemiacetal with aromatic ketones proceeds to produce ( R )-β-hydroxy β-trifluoroalkyl ketones in low to moderate yields with good enantioselectivities.

The catalytic activity of the novel title catalyst (I) is demonstrated in the highly enantioselective amination of benzofuranones with diester (III).

Simple bifunctional thioureas, derived from the commercially available saccharides and chiral diamines, have been shown tunably to promote Michael-type addition of ketones to alpha,beta-gamma,delta-nitrodienes. The Michael adducts were obtained in good yields albeit with high enantioselectivites (84-99% ee). Furthermore, these products can be readily transformed into more useful molecules.