Pd/Cu Dual‐Catalyzed Asymmetric Synthesis of Highly Functional All‐Carbon Quaternary Stereocenters from Vinyl Carbonates

Abstract

The challenging metal‐catalyzed asymmetric synthesis of highly functional quaternary carbon centers using decarboxylative C(sp3)−C(sp3) bond formation reactions is reported. The key substrate, a vinyl cyclic carbonate, is activated to provide concomitantly both the requisite nucleophile (by formal umpolung) and electrophile reaction partner preceding the asymmetric cross‐coupling process. A wide screening of reaction conditions, additives and catalyst precursors afforded a protocol that gave access to a series of compounds featuring densely functionalized, elusive quaternary carbon stereocenters in appreciable yield and with enantiomeric ratios (er's) of up to 90 : 10.

Vinyl and Alkynyl Substituted Heterocycles as Privileged Scaffolds in Transition Metal Promoted Stereoselective Synthesis

“…Finally, the enantioselective version of the VCC-cross-coupling process of Scheme a (compounds 7 ) was studied . The presence of sterically demanding chiral ligands such as the optimized L* (Scheme , a BIPHEP (6,6′-dimethoxybiphenyl-2,2′-diyl)­bis­(diphenylphosphine) based one) further challenged efficient cross-coupling.…”

Recent Applications on Dual-Catalysis for C–C and C–X Cross-Coupling Reactions

“…The required Pd catalyst was synthesized from ( R )-3,5- i Pr 2 -4-NMe 2 -MeOBIPHEP, which was proved to be effective to achieve good enantiomeric excess ( ee ), as depicted in Scheme 14 . 79…”

Biocatalytic stereoselective synthesis of pyrrolidine-2,3-diones containing all-carbon quaternary stereocenters

“…Hence, the synthesis of these frameworks is often desirable but faces many challenges. [1][2][3][4][5][6][7][8][9] Likewise, five-membered nitrogen heterocycles are important due to their numerous biological and pharmacological properties. [10][11][12][13] The combination of these heterocycles with quaternary stereocenters is particularly highly regarded due to their presence in many alkaloids.…”