The highly catalytic asymmetricα‐hydroxylation of 1‐tetralone‐derivedβ‐keto esters and β‐keto amides using tert‐butyl hydroperoxide (TBHP) as the oxidant was realized by a chiral N,N′‐dioxide‐magnesium ditriflate [Mg(OTf)2] complex. A series of corresponding chiral α‐hydroxy dicarbonyl compounds was obtained in excellent yields (up to 99%) with excellent enantioselectivities (up to 98% ee). The products
A simple and highly efficient N,Nâ²-dioxide organocatalyst system was developed for the asymmetric α-chlorination of cyclic β-ketoesters using easily available NCS as the chlorine source to provide a series of optically active α-chloro-β-ketoesters in excellent yields with 90â98% ee.