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.
Chiral sulfoxide-olefin ligands: Tunable stereoselectivity in Rh-catalyzed asymmetric 1,4-additions
Chen, Guihua,Gui, Jiangyang,Cao, Peng,Liao, Jian
supporting information; experimental part, p. 3220 - 3224 (2012/06/01)
A class of chiral sulfoxide-olefins were designed and synthesized through concise routes. Their applications as ligands in Hayashi-Miyaura reaction were studied, which found that vinyl substituents of the ligands vary in stereocontrolling ability. Particularly, either isomer of adducts with excellent ees could be readily obtained through changing the position of the substituents of olefins as well as changing the configuration of the CC bond of the ligands. Meanwhile, the substrate scope of arylboronic acids and alkenes was clearly shown.