Enantioselective synthesis of axially chiral sulfur-containing biaryl derivatives through the electrophilic sulfenylation of biaryl phenols has been achieved for the first time. This catalyticasymmetric system, which involves sequential desymmetrization and kinetic resolution, is enabled by a combination of a novel 3,3′-disubstituted BINOL-derived selenide catalyst and an achiral sulfonic acid. Control experiments
ACCESS TO CHIRAL BISPHENOL (BPOL) LIGANDS THROUGH DESYMMETRIZING ASYMMETRIC ORTHO-SELECTIVE MONO-HALOGENATION
申请人:The Chinese University of Hong Kong
公开号:US20210300853A1
公开(公告)日:2021-09-30
The subject invention pertains to a method of halogenating phenols, yielding a range of halogenated phenols with enantiomeric ratio of up to 99.5:0.5. In certain embodiments, the subject invention pertains to a method of asymmetric halogenation of bisphenol, yielding a range of chiral bisphenol ligands. The novel chiral bisphenols are potent privileged catalyst cores that can be applied to the preparation of ligands for various catalytic asymmetric reactions. The catalyst library can easily be accessed because late-stage modification of the scaffold can readily be executed through cross-coupling of the halogen handles on the bisphenols.
highly enantioselectivesynthesis of multisubstituted biarylchlorides/iodides by sequentialhalogenation reactions (desymmetrization/kinetic resolution sequence). The selectivity of biarylchlorides/iodides obtained in the first asymmetric reaction (desymmetrization) could be enhanced by the kinetic resolution‐type asymmetric bromination to afford the corresponding chiralbiarylchlorides/iodides in excellent
Described herein is the enantioselective synthesis of multisubstituted biaryl derivatives by chiral phosphoric acidcatalyzed asymmetric bromination. Two asymmetric reactions (desymmetrization and kineticresolution) proceeded successively to afford chiral biaryls in excellent enantioselectivities (up to 99% ee). Both experimental and computational studies suggested that this excellent selectivity
We describe herein the “1H NMR-assisted catalyst screening method,” which enables us to find the suitable catalyst easily and predict enantioselectivity with the same accuracy as the computational method. Based on this method, we constructed multisubstituted biaryls that occur frequently in many biologically active compounds, chiral ligands, and organocatalysts, with excellent enantioselectivities via chiral phosphoric acid-catalyzed asymmetric bromination.