Won-Yeob Kim

Tandem Cycloaddition Reactions of Allenyl Diazo Compounds Forming Triquinanes via Trimethylenemethane Diyls

A tandem reaction strategy for forming triquinanes from linear allenyl diazo compounds through an intramolecular 1,3-dipolar cycloaddition reaction of an allenyl diazo group that generates a trimethylenemethane (TMM) diyl followed by an intramolecular [2 + 3] TMM diyl cycloaddition reaction has been developed. The new tandem cycloaddition reaction is readily applicable to the synthesis of complex molecules with high versatility and efficiency.

Palladium-catalyzed coupling and carbonylative coupling of silyloxy compounds with hypervalent iodonium salts

Abstract Arylation and alkenylation of 1-ethoxy-1-trimetylsilyloxycyclopropane with diphenyliodonium tetrafluoroborate and alkenyliodonium tetrafluoroborate were accomplished by slow addition of silyloxycyclopropane to iodonium salts in the presence of Pd(OAc)2 (2 mol %) and DME H 2 O (4:1) to afford β-substituted ester. Alternatively, carbonylative coupling of silyloxypropane was carried out by slow addition of silyloxypropanes to iodonium salts under CO(1 atm) at room temperature in aqueous medium. The palladium-catalyzed coupling of ketene trimethylsilyl acetals with iodonium salts is also described.

Structure-activity relationship studies of the chromosome segregation inhibitor, Incentrom A.

A series of Incentrom A analogs that inhibit the chromosome segregation process in yeast were synthesized and tested for their effects on chromosome stability and cell proliferation. Pharmacophore and structure-activity relationship of Incentrom A for the anti-yeast activity were established.

Manganese chloride-catalyzed cross-coupling and carbonylative cross-coupling of organostannanes with iodonium salts

The MnCl2·4H2O-catalyzed cross-coupling and carbonylative cross-coupling of organo-stannanes with hypervalent iodonium salts afforded biaryls and biaryl ketones, respectively.

Total Synthesis of Ceratopicanol through Tandem Cycloaddition Reaction of a Linear Substrate

Total synthesis of ceratopicanol (1) was achieved with a tandem cycloaddition reaction of allenyl diazo compound 6 via a trimethylenemethane (TMM) diyl intermediate. The TMM diyl mediated [2+3] cycloaddition reaction furnished the consecutive quaternary carbon centers and showed an unusual diastereoselectivity.

PALLADIUM-CATALYZED CROSS-COUPLING OF CR(CO)3-COMPLEX CHLOROARENES WITH ORGANOFLUOROSILANES

Abstract The palladium-catalyzed cross-coupling of (η6 -chlorobenzene) tricarbonylchromium complexes with organofluorosilanes followed by decomplexation afforded aryl-, alkenyl-, and alkynyl-substituted arenes.

Palladium-catalyzed alkoxycarbonylation of aryl- and alkenyl-iodonium salts

The palladium-catalyzed carbonylation of diaryliodonium tetrafluoroborates and tosylates (toluene-p-sulfonates) in the presence of methanol and phenol afforded aromatic esters at room temperature under one atmosphere of carbon monoxide. However, carbonylation of diaryliodonium triflates and bromides in methanol afforded 4-iodophenyl-substituted methyl esters.