63209-59-6Relevant academic research and scientific papers
Highly enantioselective transfer hydrogenation catalyzed by diasteromeric mixtures of axially chiral (aR,S)- and (aS,S)-Biscarbolines
Dong, Mengxian,Gao, Xinyue,Xiang, Ying,Li, Longfei,Li, Shengnan,Wang, Xuxin,Li, Zhenqiu,Zhu, Huajie
supporting information, (2021/02/05)
The mixtures of axially chiral (aR,S)- and (aS,S)-biscarboline alcohols were firstly used as catalysts in enantioselective 1,2- and 1,4-transfer hydrogenations of ketimines and β-enamino esters, respectively. This mixed axially chiral catalysts exhibited
Chiral Br?nsted Acid-Catalyzed Metal-Free Asymmetric Direct Reductive Amination Using 1-Hydrosilatrane
Skrypai, Vladislav,Varjosaari, Sami E.,Azam, Fawwaz,Gilbert, Thomas M.,Adler, Marc J.
, p. 5021 - 5026 (2019/05/10)
The asymmetric direct reductive amination of prochiral ketones with aryl amines using 1-hydrosilatrane with a chiral Br?nsted acid catalyst is reported. This is the first known example of chiral Br?nsted acid-catalyzed asymmetric reductive amination using
Synthesis and application of axially chiral biscarbolines with functional N-O and sulfone for 1,2-transfer hydrogenations of ketimines
Xing, Yongfei,Wu, Shijie,Dong, Mengxian,Wang, Jie,Liu, Li,Zhu, Huajie
, (2019/08/08)
A series of axially chiral biscarboline-based sulfones were synthesized from L-tryptophane and applied for enantioselective 1,2-transfer hydrogenations of ketimines using trichlorosilane. The catalyst 4e, which had a tertiary butyl group, exhibited a good conversion and high enantioselectivities up to 96%ee in the series of reactions.
Catalytic Mechanism Study on the 1,2- and 1,4-Transfer Hydrogenation of Ketimines and β-Enamino Esters Catalyzed by Axially Chiral Biscarboline-Based Alcohols
Dong, Mengxian,Wang, Jie,Wu, Shijie,Zhao, Yang,Ma, Yangyang,Xing, Yongfei,Cao, Fei,Li, Longfei,Li, Zhenqiu,Zhu, Huajie
supporting information, p. 4602 - 4610 (2019/08/30)
Axial N-O alcohols, which have two large carboline moieties connected to the axis were synthesized and used in catalytic enantioselective 1,2- and 1,4-transfer hydrogenations of total 26 ketimines and β-enamino esters. Excellent levels of enantioselectivity ranging from 91% to 99% were achieved by using catalyst (aS)-(S)-3,3′-bis((S)-2-(hydroxymethyl)pyrrolidine-1-carbonyl)-9,9′-dimethyl-9H,9′H-[1,1′-bipyrido[3,4-b]indole] 2-oxide. Interestingly, a mixture of (aS)-(S)-3,3′-bis((S)-2-(hydroxymethyl)pyrrolidine-1-carbonyl)-9,9′-dimethyl-9H,9′H-[1,1′-bipyrido[3,4-b]indole] 2-oxide and (aR)-(S)-3,3′-bis((S)-2-(hydroxymethyl)pyrrolidine-1-carbonyl)-9,9′-dimethyl-9H,9′H-[1,1′-bipyrido[3,4-b]indole] 2-oxide was also able to provide high enantioselectivities up to 95% that is the same as that using pure (aS)-(S)-3,3′-bis((S)-2-(hydroxymethyl)pyrrolidine-1-carbonyl)-9,9′-dimethyl-9H,9′H-[1,1′-bipyrido[3,4-b]indole] 2-oxide. A plausible catalytic mechanism was suggested and total four kinds of transition states (TS) including almost 60 TS structures were investigated using density functional theory (DFT) with different basis sets such as 6-311G(2d,p). The predicted activation energy data are consistent with the experimental results. (Figure presented.).
P-Stereogenic and Non-P-Stereogenic Ir-MaxPHOX in the Asymmetric Hydrogenation of N -Aryl Imines. Isolation and X-ray Analysis of Imine Iridacycles
Salomó, Ernest,Rojo, Pep,Hernández-Lladó, Pol,Riera, Antoni,Verdaguer, Xavier
, p. 4618 - 4627 (2018/04/26)
A small library of Ir-MaxPHOX catalysts has been applied to the asymmetric hydrogenation of N-aryl imines. A structure-activity analysis of the three-chiral-center MaxPHOX ligand has been performed. Using complex 1b, the hydrogenation of N-aryl imines too
Asymmetric hydrogenation of imines with chiral alkene-derived boron Lewis acids
Liu, Xiaoqin,Liu, Ting,Meng, Wei,Du, Haifeng
supporting information, p. 8686 - 8689 (2018/11/30)
With the aim of developing easily accessible chiral Lewis acids for asymmetric hydrogenation, a variety of binaphthyl-based chiral alkenes were prepared in one step from the corresponding diols. Using the in situ generated chiral boron Lewis acids through
NOVEL PICOLINAMIDE-CINCHONA ORGANOCATALYSTS AND DERIVATIVES
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Paragraph 0058, (2016/09/12)
The present application describes a novel type of picolinamide-cinchona organocatalyst that allows for the successful transformation of ketimines to chiral amines with very high enantioselectivities and with the highest TOFs reported for any particular organocatalyst to date. These organocatalysts have also been immobilized to a variety of solid supports, including magneto-nanoparticles.
Cinchona-Derived Picolinamides: Effective Organocatalysts for Stereoselective Imine Hydrosilylation
Barrulas, Pedro C.,Genoni, Andrea,Benaglia, Maurizio,Burke, Anthony J.
, p. 7339 - 7342 (2016/02/20)
Picolinamide-cinchona organocatalysts for the successful enantioselective reduction of ketomines were developed. For the first time, a new type of chiral Lewis base, a cationic species, is reported to efficiently organocatalyze the addition of trichlorosi
Chiral phosphoric-acid-catalyzed transfer hydrogenation of ethyl ketimine derivatives by using benzothiazoline
Saito, Kodai,Horiguchi, Kosaku,Shibata, Yukihiro,Yamanaka, Masahiro,Akiyama, Takahiko
, p. 7616 - 7620 (2014/07/07)
Chiral phosphoric acid catalyzed transfer hydrogenation of ketimines derived from propiophenone derivatives and reductive amination of alkyl ethyl ketone derivatives were extensively examined in the presence of two representative hydrogen donors. The exce
Novel carbohydrate-derived pyridinecarboxylic organocatalysts for the enantioselective reduction of imines with trichlorosilane
Ge, Xin,Qian, Chao,Chen, Yunbin,Chen, Xinzhi
, p. 596 - 601 (2014/05/20)
A new type of carbohydrate-derived pyridinecarboxylic organocatalyst was prepared by fine-tuning a d-glucosamine backbone at the C-2 and C-3 positions. The carbohydrate-derived pyridinecarboxylic organocatalyst was used for the enantioselective reduction of imines with trichlorosilane. The reduction proceeded in high yield (up to 93%) and with moderate enantioselectivity (up to 75%).
