The Cu(MeCN) PF /DTBM-Segphos complex catalyzed the highly diastereo- and enantioselective 1,3-dipolar cycloaddition of azomethine ylides with benzo[b]thiophene sulfones with the usual regiochemistry to give single isomers of the exo-cycloadducts in good yields. In contrast, the AgOAc/ThioClickFerrophos complex catalyzed the reaction with atypical regiochemistry to give the endo-cycloadducts as major products with excellent enantioselectivities. Thus, the choice of chiral metal complex enabled the regio- and stereoselective synthesis of chiral fused sulfolanes.

A AgOAc/ThioClickFerrophos complex-catalyzed the highly diastereo- and enantioselective reaction between 1-pyrroline-5-carboxylates (1) and acyclic α-enones (2) in MeOH, in the presence of DBU, to give the single isomer Michael adducts (3) in high yields (up to 99%) with excellent enantioselectivies (up to 99% ee). Subsequent reduction of the Michael adducts with sodium cyanoborohydride successfully produced the fused pyrrolizidine ester as an almost pure single stereoisomer.

We have developed palladium-catalyzed C–H activation and cyclization of alkynyl ferrocenyl ethers with various alkynes, providing ferrocene-fused pyran derivatives. As a preliminary result, we also achieved the asymmetric version of this reaction with high enantioselectivity, providing the first example of the catalytic asymmetric synthesis of an enantio-enriched ferrocene-fused oxacycle.

The liquid phase autoxidation of isobutyraldehyde to peroxyisobutyric acid was investigated with ozone as an initiator. The selectivity of the peroxyacid increases with decrease in the amount of aldehyde converted per unit volume of reacting fluid, increase in the ozone feed rate, and decrease in temperature. A few percent of water in solvents increases the selectivity, although too much water brings about a reverse effect. Isopropyl alcohol, acetone, isopropyl formate, propane, propylene, carbon dioxide, and carbon monoxide are observed as by-products besides isobutyric acid. Purified peroxyisobutyric acid (97.2 wt%) was obtained by fractionally distilling the autoxidation product and some of its physical properties were determined. The utility of the peroxyacid as an epoxidizing agent is described.

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