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A study was conducted to analyze a transition-metal-catalyzed diastereo- and enantioselective 1,3-dipolar cycloaddition reaction between electrophilic nitrones and electron-rich alkenes. The rection supported chiral copper(II)- and zinc(II)-bisoxazolines as catalysts. Results indicated that the coordination of nitrone and alkene to the chiral copper(II)-bisoxazoline catalyst correlates with the intermediate.

Succinimide was utilized as an auxiliary of the alpha, beta-unsaturated carbonyl moiety for the metal-catalyzed asymmetric 1,3-dipolar cycloaddition reactions between alpha, beta-unsaturated carbonyls and acyclic nitrones. Succinimide significantly improved the diastereo- and enantioselectivity of the 1,3-dipolar cycloaddition reaction of nitrones with alkenes using Ti-TADDOLates as the catalysts. The reaction led to the formation of exo-isoxazolidines with high a 3R, 4T, 5S configuration.

The development of general conditions for the use of a simple electrophilic vinylation reagent, represented by vinyl tosylate, in the Pd(0)-catalyzed Suzuki-Miyaura coupling reaction with arylboronic acids is reported. The method could be expanded to provide a simple approach to introduce gem-difluorovinyl substituent onto an aromatic ring using readily available 2,2-difluorovinyl tosylate as the electrophilic complement.

An alternative protecting group, the trifluoroacetyl moiety was developed for guanidine functionality. The protecting group, which is easily cleaved under mild conditions, can be applied to peptide synthesis in solution as well as on a solid support.

The first highly diastereo- and enantioselective catalytic 1,3-dipolar cycloaddition reaction of cyclic nitrones activated by chiral Lewis acids with electron-rich alkenes has been developed. The mechanism of reaction is discussed on the basis of the assignment of the absolute configuration of the cycloaddition product and theroetical calculations.