Enantioselective Preparation of 8-Oxabicyclo[3.2.1]octane Derivatives via Asymmetric [3+2]-Cycloaddition of Platinum-Containing Carbonyl Ylides with Vinyl Ethers

Abstract

A catalytic asymmetric synthesis of 8-oxabicyclo[3.2.1]octane derivatives was achieved through the [3+2]-cycloaddition of the platinum-containing carbonyl ylides generated from acyclic gamma,delta-ynones on treatment with 10 mol % of PtCl(2)-Walphos and AgSbF(6). Synthetically useful 8-oxabicyclo[3.2.1]octane derivatives were obtained in good yields and mostly in over 90% ee's.

Multiformat T‐Cell‐Engaging Bispecific Antibodies Targeting Human Breast Cancers

“…(Scheme , complex C ). A third option consisting of the combination of a chiral neutral bidentate ligand and an anionic monodentate ligand leads to the formation of monocationic platinum complexes that have found application in the cycloaddition of alkynones with alkenes14 (Scheme , complex D ).…”

Chiral Copper(II) Phosphate Catalyzed Enantioselective Synthesis of Isochromene Derivatives by Sequential Intramolecular Cyclization and Asymmetric Transfer Hydrogenation of o‐Alkynylacetophenones

“…[3] The cationic metallic intermediate can form a tight ion pair with the chiral counteranion. [7] There are no preceding examples for enantiocontrol of the carbonyl ylide intermediate using the ACDC concept, and the development of asymmetric reactions using metal-containing carbonyl ylide intermediates based on the new concept is thus, an important challenge.More recently, Yao and co-workers reported the Pd(OAc) 2 / CPA-catalyzed asymmetric cascade annulation based on an oxa-Diels-Alder cycloaddition using a metal-containing carbonyl ylide intermediate to afford tetrahydronapthalene derivatives with multiple stereogenic centers including quaternary carbon atoms, thus taking advantage of the metallo/ organo binary catalytic methodology. Recently, reactions initiated by alkyne activation, combined with the use of CPA have also been developed.…”

“…[3] The cationic metallic intermediate can form a tight ion pair with the chiral counteranion. [7] There are no preceding examples for enantiocontrol of the carbonyl ylide intermediate using the ACDC concept, and the development of asymmetric reactions using metal-containing carbonyl ylide intermediates based on the new concept is thus, an important challenge. Recently, reactions initiated by alkyne activation, combined with the use of CPA have also been developed.…”

Recent developments in gold-catalyzed cycloaddition reactions

“…In particular, important developments were recently achieved with platinum catalysts [36–37], including the first enantioselective examples of these type of cycloadditions promoted by a chiral cationic platinum–diphosphine catalyst [38]. …”