Catalytic Asymmetric Transfer Hydrogenation of <i>trans</i>-Chalcone Derivatives Using BINOL-derived Boro-phosphates
作者:Fei Na、Susana S. Lopez、Alice Beauseigneur、Lucas W. Hernandez、Zhuoxin Sun、Jon C. Antilla
DOI:10.1021/acs.orglett.0c02042
日期:2020.8.7
Chiral phosphoric-acid-catalyzed asymmetric reductions of trans-chalcones have been investigated in this work. A BINOL-derived boro-phosphate-catalyzed asymmetric transfer hydrogenation of the carbon–carbon double bond of trans-chalcone derivatives employing borane as a hydride source was realized. This methodology provides a convenient procedure to accesschiral dihydrochalone derivatives in high
Catalytic asymmetric construction of tetrasubstituted carbon stereocenters by conjugate addition of dialkyl phosphine oxides to β,β-disubstituted α,β-unsaturated carbonyl compounds
作者:Depeng Zhao、Lijuan Mao、Linqing Wang、Dongxu Yang、Rui Wang
DOI:10.1039/c1cc16079f
日期:——
The catalytic asymmetric phospha-Michael reaction of dialkyl phosphine oxides with beta,beta-disubstituted alpha,beta-unsaturated carbonyl compounds was achieved. The products bearing tetrasubstituted carbon stereocenters were obtained in high yields with excellent enantioselectivities (up to >99% ee).
A succinct and efficient protocol was developed for the synthesis of chiral aromatic ketones via asymmetric hydrogenation of β,β-disubstitutedenones with rhodium catalysts based on chiral bisphosphine thiourea ligands. A series of substrates (17 examples) was smoothly catalyzed to afford the corresponding chiral aromatic ketones in high conversions(>99%)with excellent enantioselectivities (up to 96%
Direct Aroylation of Olefins through a Cobalt/Photoredox‐Catalyzed Decarboxylative and Dehydrogenative Coupling with α‐Oxo Acids
作者:Alex M. Davies、Rafael D. Hernandez、Jon A. Tunge
DOI:10.1002/chem.202202781
日期:2022.12.27
Visible light promotes decarboxylative Heck-like benzoylations of olefins. This process leverages the synergistic interaction of a photoredox catalyst with cobaloxime catalysts to form enones through decarboxylation and hydrogen evolution. Mechanistic studies reveal different rate-limiting steps, depending on electronics of the olefin.