Optically active compound preparation by intramolecular Stetter reaction

摘要

Preparation of optically active compounds (I) comprises an intramolecular Stetter reaction of compound with an aldehyde function and an activated carbon-carbon (C-C) double bond, using a chiral Stetter 4,5-dihydro-1H-1,2,4-triazolium-5-ylide catalyst of formula (II) in an inert solvent. R1, R3 = alkyl or aryl, at least one of which is chiral; R2 = H, alkyl, aryl, halo, perfluoroalkyl, alkoxy, phenoxy, arylthio, R2N (sic), CN or NO2. In a dependent claim, R2+R3 may complete a ring.