Journal of the American Chemical Society published new progress about Allylic alkylation catalysts, stereoselective. 152140-65-3 belongs to class chiral-phosphine-ligands, and the molecular formula is C54H42N2O2P2, COA of Formula: C54H42N2O2P2.
Trost, Barry M.; Xu, Jiayi; Schmidt, Thomas published the artcile< Palladium-Catalyzed Decarboxylative Asymmetric Allylic Alkylation of Enol Carbonates>, COA of Formula: C54H42N2O2P2, the main research area is allyl enol carbonate enantioselective regioselective decarboxylative allylic alkylation palladium; ketone homoallylic asym synthesis.
Palladium-catalyzed decarboxylative asym. allylic alkylation (DAAA) of allyl enol carbonates as a highly chemo-, regio-, and enantioselective process for the synthesis of ketones bearing either a quaternary or a tertiary α-stereogenic center has been investigated in detail. Chiral dibenzobarrelene-based diphosphine ligand was found to be optimal in the DAAA of a broad scope of cyclic and acyclic ketones including simple aliphatic ketones with more than one enolizable proton. The allyl moiety of the carbonates has been extended to a variety of cyclic or acyclic disubstituted allyl groups. The mechanistic studies revealed that, similar to the direct allylation of lithium enolates, the DAAA reaction proceeds through an “”outer sphere”” SN2 type of attack on the π-allylpalladium complex by the enolate. An important difference between the DAAA reaction and the direct allylation of lithium enolates is that in the DAAA reaction, the nucleophile and the electrophile were generated simultaneously. Since the π-allylpalladium cation must serve as the counterion for the enolate, the enolate probably exists as a tight-ion-pair. This largely prevents the common side reactions of enolates associated with the equilibrium between different enolates. The much milder reaction conditions as well as the much broader substrate scope also represent the advantages of the DAAA reaction over the direct allylation of preformed metal enolates.
Journal of the American Chemical Society published new progress about Allylic alkylation catalysts, stereoselective. 152140-65-3 belongs to class chiral-phosphine-ligands, and the molecular formula is C54H42N2O2P2, COA of Formula: C54H42N2O2P2.
Referemce:
Phosphine ligand,
Chiral phosphine ligands in asymmetric synthesis. Molecular structure and absolute configuration of (1,5-cyclooctadiene)-(2S,3S)-2,3-bis(diphenylphosphino)butanerhodium(I) perchlorate tetrahydrofuran solvate