Palladium‐Catalyzed Enantioselective Thiocarbonylation of Styrenes

Abstract

Ah ighly enantioselective thiocarbonylation of styrenes with CO and thiols has been achieved by Pd catalysis, providing highly enantioenriched thioesters in good to excellent yields.Key to the successful execution of this reaction is the use of achiral sulfoxide-(P-dialkyl)-phosphine (SOP) ligands. This thiocarbonylation proceeds smoothly under mild reaction conditions (1 atm CO and 0 8 8C) and displays broad substrate scope.A lso demonstrated is that this transformation can be conducted using surrogates of CO,greatly increasing the safety aspects of running the reaction. The generality and utility of the method is manifested by its application to the synthetic transformations of thioester products and the direct acylation of cysteine-containing dipeptides.Ap rimary mechanism was investigated and aplausible catalytic cycle was proposed. Scheme 1. Pd-catalyzed enantioselective thiocarbonylation of alkenes. Supportinginformation and the ORCID identification number(s) for the author(s) of this article can be found under: https://doi.Scheme 7. Proposed catalytic cycle.Figure 2. X-ray structure and DFT calculation.

Diastereoselective Alkene Hydroesterification Enabling the Synthesis of Chiral Fused Bicyclic Lactones

“…Palladium‐catalysed asymmetric alkoxycarbonylation of alkenes allows for the efficient conversion of widely available alkene compounds, CO and alcohols into the corresponding chiral carboxylic acid derivatives [24–28] . Although the intramolecular asymmetric carbonylation of allylic alcohols has been utilized to obtain chiral γ‐butyrolactone compounds, [29,30] the demand on preparing such motif bearing derivatizable functional group, which can be employed as the intermediate of assembling chiral THF‐fused γ‐lactone unit, was yet to be solved.…”

Recent Advances for Chiral Sulfoxides in Asymmetric Catalysis

“…In 2019, Liao and coworkers reported a chiral sulfoxide-(P-dialkyl)phosphine (SOP) ligand L73 in palladium-catalyzed enantioselective thiocarbonylation of sytrenes, which delivered high enantiomeric enrichment of thioesters in good to excellent yields (Scheme 41). [63] On the basis of the study, a rational catalytic cycle was proposed for the Pd-catalyzed thiocarbonylation of in the presence of chiral sulfoxide-(P-dialkyl)-Phosphine (SOP). Starting with the production of Pd(0) species A from Pd2dba3 and SOP, the oxidative addition of Pd(0) to p-TsOH gave Pd(II)-H species B. Pd(II)-H species coordinated with styrene to provide Synthesis Review / Short Review In 2020, Lei and Liao developed chiral sulfoxide phosphine (SOP) ligands in palladium(II)-catalyzed enantio-selective hydrofluorination of alkenylarenes (Scheme 42) [64] , which gave a range of chiral benzyl fluorides with different functional groups in good yields (up to 80%) and high enantiomeric purity (up to 94:6 enantiomeric ratio).…”

“…In 2019, Liao and co-workers reported chiral SOP ligand L83 in the Cu-catalyzed S N 2′ substitution of propargyl phosphates with vinyl-derived chiral nucleophiles (Scheme 47 ). 69 This method provides an efficient and enantioselective approach to access a range of optically pure di- (1,1-), tri-, and tetrasubstituted allenes with α-central chirality and axial chirality in excellent chemo-, regio-, diastereo-, and enantioselectivities. There was no significant chiral matching/mismatching effect observed when two absolutely conformationally opposite SOP ligands were used.…”

Umpolung Asymmetric 1,5‐Conjugate Addition via Palladium Hydride Catalysis

“…Recently, considerable progress has been achieved in transition metal‐catalyzed asymmetric hydrofunctionalizations [22, 23] of conjugated dienes [24–48] . We thus envisioned that the long‐time unsolved umpolung nucleophilic 1,5‐addition might be realized if suitably defined palladium hydride catalysis [49–60] was identified (Scheme 1b). However, classical hydrofunctionalizations of conjugated dienes are limited to the use of inert aryl and alkyl units as substituents [22–48] .…”