Diastereoselective formal [3 + 3] cycloaddition of isatin-based α-(trifluoromethyl)imines with N,N′-dialkyloxyureas

Abstract

In the presence of PhI(OH)(OTs) and NaH, the diastereoselective formal [3 + 3] cycloaddition of isatin-based α-(trifluoromethyl)imines with N,N′-dialkyloxyureas proceeded readily, and furnished the relatively trans-configured novel spiro-1,3,5-triazinan-2-ones in reasonable chemical yields. The relative stereochemical configuration of the target products was clearly identified by X-ray diffraction analysis.