Direct Asymmetric α-Hydroxylation of Cyclic α-Branched Ketones through Enol Catalysis
作者:Benjamin List、Grigory Shevchenko、Gabriele Pupo
DOI:10.1055/s-0037-1611084
日期:2019.1
Enantiopure α-hydroxy carbonyl compounds are common scaffolds in natural products and pharmaceuticals. Although indirect approaches towards their synthesis are known, direct asymmetric methodologies are scarce. Herein, we report the first direct asymmetric α-hydroxylation of α-branchedketones through enol catalysis, enabling a facile access to valuable α-keto tertiary alcohols. The transformation
An Unexpected α‐Oxidation of Cyclic Ketones with 1,4‐Benzoquinone by Enol Catalysis
作者:Grigory A. Shevchenko、Barry Oppelaar、Benjamin List
DOI:10.1002/anie.201804445
日期:2018.8.13
The first direct and asymmetric α‐aryloxylation of cyclic ketones via enol catalysis has been achieved using quinones as the reaction partners. Catalytic amounts of a phosphoric acid promote the exclusive formation of α,α‐disubstituted ketones from the corresponding α‐substituted ketones in good yields and enantioselectivities (up to 96.5:3.5 er). Preliminary mechanistic experiments suggest that this