A cationic oxazaborolidinium-catalyzed asymmetric Mukaiyama aldol reaction of (1-methoxy-2-methyl-propenyloxy)-trimethylsilane with various aldehydes including α,β-disubstituted acroleins has been developed in high yields and enantioselectivities. The synthetic utility of this methodology was demonstrated in the first short synthesis of naturally occurring inthomycin C in high enantiopurity.

Chiral oxazaborolidinium ion-catalyzed Csp(2)-H functionalization of enones using diazoacetate has been developed. Various β-substituted cyclic enones were synthesized in high yield (up to 99%) with high to excellent enantioselectivity (up to 99% ee). The synthetic utility of this reaction was demonstrated by the formal synthesis of (+)-epijuvabione.

The first example of the boron Lewis acid catalyzed C(sp2)-H functionalization of cyclic enones was achieved using diazoacetates. The insertion of the carbon atom of diazoacetates utilizes BF3•Et2O or a newly designed oxazaborolidinium ion as a catalyst to afford β-functionalized cyclic enones from simple cyclic enones in a single step and high yields. The reaction mechanism was investigated with deuterium labeled 2-cyclohexen-1-one.

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A geometric-selective synthesis of (E)-beta-iodo Morita-Baylis-Hillman esters has been developed through a three-component aldol-type reaction using BF3.Et2O and TMS-I. The synthetic utility of the (E)-beta-iodo Morita-Baylis-Hillman esters was demonstrated in the first reported short synthesis of secokotomolide A.

Total synthesis of (+)-ambuic acid has been accomplished from the readily available stereocontrolled Diels-Alder adduct of cyclopentadiene and iodo-1,4-benzoquinone monoketal through an efficient series of steps. A new method for the highly commendable synthesis of α-brominated Diels-Alder adduct is described.

Highly enantioselective 1,3-dipolar cycloaddition reactions of α-substituted diazoacetates are accomplished by catalysis of the chiral oxazaborolidinium ion. Functionalized 2-pyrazolines are synthesized in high to excellent enantiomeric ratios (up to >99 : 1). The synthetic utility of 2-pyrazoline was expanded via preparation of 2,4-diamino ester compounds bearing a chiral quaternary carbon center.

A simple and efficient method for the asymmetric synthesis of α-alkylidene-β-hydroxy-γ-butyrolactones and related natural products was developed on the basis of the catalytic asymmetric tandem Michael-aldol reaction and simple transformations. The synthetic utility of this method was illustrated by the facile synthesis of trisubstituted γ-butyrolactone natural products.