1010458-26-0Relevant articles and documents
Aqueous Asymmetric 1,4-Addition of Arylboronic Acids to Enones Catalyzed by an Amphiphilic Resin-Supported Chiral Diene Rhodium Complex under Batch and Continuous-Flow Conditions
Shen, Guanshuo,Osako, Takao,Nagaosa, Makoto,Uozumi, Yasuhiro
, p. 7380 - 7387 (2018)
A rhodium-chiral diene complex immobilized on amphiphilic polystyrene-poly(ethylene glycol) (PS-PEG) resin (PS-PEG-diene?-Rh) has been developed. The immobilized rhodium-chiral diene complex (PS-PEG-diene?-Rh) efficiently catalyzed the asymmetric 1,4-addition of various arylboronic acids to cyclic or linear enones in water under batch conditions to give the corresponding β-arylated carbonyl compounds in excellent yields and with excellent enantioselectivity. The catalyst was readily recovered by simple filtration and reused 10 times without loss of its catalytic activity and enantioselectivity. Moreover, a continuous-flow asymmetric 1,4-addition in a flow reactor containing PS-PEG-diene?-Rh proceeded efficiently at 50 °C with retention of high enantioselectivity. Long-term continuous-flow asymmetric 1,4-addition during 12 h readily gave the desired product on a 10 g scale with high enantioselectivity.
Chiral sulfinyl-based olefin ligands for rhodium-catalysed asymmetric conjugate addition of arylboronic acids to cyanoalkenes
Xue, Feng,Zhu, Yong,Qi, Xiaolei
, p. 300 - 304 (2018/08/03)
A rhodium/sulfinyl-based olefin ligand-catalysed asymmetric conjugate addition of arylboronic acids to cyanoalkenes without activation groups has been developed, where p-tolylsulfinyl-functionalised olefin ligands have been shown to be effective and with moderate enantioselectivities. This is the first example of applying chiral sulfinyl-based olefin ligands in the catalytic asymmetric addition to cyanoalkenes.
Highly efficient Rh-catalyzed asymmetric hydrogenation of α,β-unsaturated nitriles
Yan, Qiaozhi,Kong, Duanyang,Li, Meina,Hou, Guohua,Zi, Guofu
supporting information, p. 10177 - 10181 (2015/09/01)
A highly efficient enantioselective hydrogenation of α,β-unsaturated nitriles catalyzed by Rh-(R,R)-f-spiroPhos complex has been developed. With Rh-(R,R)-f-spiroPhos catalyst and under mild conditions, a wide range of α,β-unsaturated nitriles including the (E)- and (Z)-isomers of 3-alkyl-3-aryl, 3,3-diaryl, and 3,3-dialkyl α,β-unsaturated nitriles were hydrogenated to the corresponding chiral nitriles with excellent enantioselectivities (up to 99.9% ee) and high turnover numbers (TON up to 10,000).
Copper-catalyzed 1,4-addition of organoboronates to alkylidene cyanoacetates: Mechanistic insight and application to asymmetric catalysis
Takatsu, Keishi,Shintani, Ryo,Hayashi, Tamio
supporting information; experimental part, p. 5548 - 5552 (2011/07/30)
In addition: A copper/N-heterocyclic carbene(NHC)-catalyzed 1,4-addition of organoboronates to alkylidene cyanoacetates was developed, in which the catalytic cycle is proposed to consist of a transmetalation/insertion/ligand exchange. An effective asymmetric variant has also been achieved by the use of a chiral NHC ligand (see scheme). Copyright
Asymmetrie synthesis of 1,1-diarylalkyl units by a copper hydride catalyzed reduction: Differentiation between two Similar aryl substituents
Yoo, Kihyun,Kim, Hyohyun,Yun, Jaesook
supporting information; experimental part, p. 11134 - 11138 (2010/04/25)
An efficient method for the preparation of enantiomerically enriched 1,1-diarylalkyl units has been developed. The use of copper hydride complexed by the (R)-1-[(5)-2-diphenylphosphino)ferrocenyl]ethyldicyclohexylphosphine (Josiphos) ligand effects a highly enantioselective conju-gate reduction of β,β-diaryl-substituted α,β-unsaturated nitriles with aryl groups of similar steric demand and no secondary coordination site. A range of substrates with meta and para substituents on the aryl group were reduced with good to excellent enantioselectivities (up to 97% enantiomeric excess (ee)) and this methodology was applied to the formal synthesis of indatraline.
