Asymmetric Allylic Alkylation of β-Ketoesters via C–N Bond Cleavage of <i>N</i>-Allyl-<i>N</i>-methylaniline Derivatives Catalyzed by a Nickel–Diphosphine System
nickel-catalyzed AAA with allylicalcohols results in low enantioselectivity. On the basis of the kinetics using a catalyst system made of Ni(cod)2 and (S)-Tol-MeO-BIPHEP, and DFT calculations for the reaction pathway of the AAA reaction mediated by an isolated olefin-coordinated nickel–DPPF complex 4b, we propose a mechanism where protonation of the nitrogen atom of the coordinating allylic amine by β-ketoester
A highly efficient α-hydroxylation of β-ketoesters catalyzed by cupreidine in the presence of cumyl hydroperoxide (CHP) was achieved. The reaction was applied to a wide variety of β-ketoesters to give products in high yields (up to 95%) with excellent enantioselectivities (up to 97% ee). The reaction had been successfully scaled up to a gram quantity and (S)-5-chloro-2-hydroxy-1-oxo-2,3-dihydro-
asymmetric α‐hydroxylation of β‐indanone esters and β‐indanone amides using peroxide as the oxidant was realized with a new C‐2′ substituted Cinchona alkaloid derivatives. The two enantiomers of α‐hydroxy‐β‐indanone esters could be obtained by simply changing the oxidant. This protocol allows a convenient access to the corresponding α‐hydroxy‐β‐indanone esters and α‐hydroxy‐β‐indanone amides with up to
An efficient and enantioselective photo-organocatalytic [small alpha]-hydroxylation of [small beta]- dicarbonyl compounds using molecular oxygen has been extended. This simple catalytic procedure is applicable to a range of [small beta]-keto esters and [small beta]-keto...