1220531-61-2Relevant articles and documents
Organic Solvent-free Asymmetric 1,4-Addition in Liquid- or Solid-State using Conventional Stirring Catalyzed by a Chiral Rhodium Complex Developed as a Homogeneous Catalyst
Korenaga, Toshinobu,Kori, Hiroto,Asai, Shota,Kowata, Ryo,Shirai, Masayuki
, p. 6059 - 6066 (2020/10/28)
Organic solvent-free asymmetric 1,4-addition of arylboronic acids to enone substrates was performed by using a chiral rhodium complex catalyst developed as a homogeneous catalyst. Reactions catalyzed by [RhOH(cod)]2 with chiral diphosphine ligands in liquid- or solid-state proceeded to give chiral 1,4-adducts in high yield with enantioselectivities up to ca. 100 % ee by conventional stirring without mechanochemistry such as ball milling. The solid-state reactions under a static condition also proceeded, but with a slight decrease in enantioselectivity of the 1,4-adduct. SEM observations of the solid-state reactions indicated that no nanoparticles catalyst was generated. The organic solvent-free reaction could be applied to gram-scale synthesis by performing a greener purification using a minimum necessary organic solvent.
Chiral Bicyclic Bridgehead Phosphoramidite (Briphos) Ligands for Asymmetric Rhodium-Catalyzed 1,2- and 1,4-Addition
Lee, Ansoo,Kim, Hyunwoo
, p. 3520 - 3527 (2016/05/24)
A complementary solution for Rh-catalyzed enantioselective 1,2- and 1,4-arylation with two structurally related chiral ligands is reported. A chiral bicyclic bridgehead phosphoramidite (briphos) ligand derived from 1-aminoindane was efficient for the 1,2-arylation of N-sulfonyl imines, while that derived from 1,2,3,4-tetrahydro-1-naphthylamine was efficient for 1,4-arylation of α,β-unsaturated cyclic ketones. For α,β-unsaturated N-tosyl ketimines, the briphos derived from 1-aminoindane was found to selectively provide γ, γ-diaryl N-tosyl enamines with high yields and stereoselectivities.
Enantioselective β-arylation of ketones enabled by lithiation/borylation/1,4-addition sequence under flow conditions
Shu, Wei,Buchwald, Stephen L.
supporting information; experimental part, p. 5355 - 5358 (2012/07/13)
The first multistep asymmetric catalysis in flow has been realized using a lithiation/borylation/rhodium-catalyzed 1,4-addition sequence. The three-step sequence starts from readily available and inexpensive aryl bromides, affording β-arylated ketones in