1217825-97-2Relevant academic research and scientific papers
Zinc-Catalyzed Asymmetric Hydrosilylation of Cyclic Imines: Synthesis of Chiral 2-Aryl-Substituted Pyrrolidines as Pharmaceutical Building Blocks
W?glarz, Izabela,Michalak, Karol,Mlynarski, Jacek
supporting information, p. 1317 - 1321 (2020/12/09)
The first successful enantioselective hydrosilylation of cyclic imines promoted by a chiral zinc complex is reported. In situ generated zinc-ProPhenol complex with silane afforded pharmaceutically relevant enantioenriched 2-aryl-substituted pyrrolidines in high yields and with excellent enantioselectivities (up to 99% ee). The synthetic utility of presented methodology is demonstrated in an efficient synthesis of the corresponding chiral cyclic amines, being pharmaceutical drug precursors to the Aticaprant and Larotrectinib. (Figure presented.).
Enantioselective Synthesis of 2-Substituted Pyrrolidines via Intramolecular Reductive Amination
Chang, Mingxin,Guo, Haodong,Huang, Haizhou,Zhang, Tao,Zhao, Wenlei,Zhou, Huan
, p. 2713 - 2719 (2019/06/19)
Catalyzed by the complex generated in situ from iridium and the chiral ferrocene ligand, tert -butyl (4-oxo-4-arylbutyl)carbamate substrates were deprotected and then reductively cyclised to form 2-substituted arylpyrrolidines in a one-pot manner, in which the intramolecular reductive amination was the key step. A range of chiral 2-substituted arylpyrrolidines were synthesised in up to 98percent yield and 92percent ee.
CHIRAL CATALYST AND METHOD FOR ASYMMETRIC REDUCTION OF AN IMINE
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Paragraph 00126; 00127, (2019/04/16)
The present disclosure discusses (i) a compound having a chemical formula according to Formula (I), or its enantiomer; and (ii) a compound that is reactive with a hydride to produce a compound having a chemical formula according to Formula (I), or its enantiomer. Formula (I) is: Formula (I) where R1 and R2 are H, optionally substituted C1-C3 alkyl, or linked together to form an optionally substituted C3 or C4 alkyl group; R3 and R3' are H; R4 and R4' are the same, and are optionally substituted C1-C6 alkyl; and R5 and R5' are the same, and are optionally substituted aryl or heteroaryl. In some examples, R4 and R5 are linked, and R4' and R5' are linked, where both linking groups are the same. The present disclosure also discusses methods of asymmetric reduction of an imine, and methods of forming the catalysts and pre-catalysts.
Enantioselective Imine Reduction Catalyzed by Phosphenium Ions
Lundrigan, Travis,Welsh, Erin N.,Hynes, Toren,Tien, Chieh-Hung,Adams, Matt R.,Roy, Kayelani R.,Robertson, Katherine N.,Speed, Alexander W. H.
supporting information, p. 14083 - 14088 (2019/10/11)
The first use of phosphenium cations in asymmetric catalysis is reported. A diazaphosphenium triflate, prepared in two or three steps on a multigram scale from commercially available materials, catalyzes the hydroboration or hydrosilylation of cyclic imin
An (R)-imine reductase biocatalyst for the asymmetric reduction of cyclic imines
Hussain, Shahed,Leipold, Friedemann,Man, Henry,Wells, Elizabeth,France, Scott P.,Mulholland, Keith R.,Grogan, Gideon,Turner, Nicholas J.
, p. 579 - 583 (2015/03/05)
Although the range of biocatalysts available for the synthesis of enantiomerically pure chiral amines continues to expand, few existing methods provide access to secondary amines. To address this shortcoming, we have over-expressed the gene for an (R)-imine reductase [(R)-IRED] from Streptomyces sp. GF3587 in Escherichia coli to create a recombinant whole-cell biocatalyst for the asymmetric reduction of prochiral imines. The (R)-IRED was screened against a panel of cyclic imines and two iminium ions and was shown to possess high catalytic activity and enantioselectivity. Preparative-scale synthesis of the alkaloid (R)-coniine (90 % yield; 99 % ee) from the imine precursor was performed on a gram-scale. A homology model of the enzyme active site, based on the structure of a closely related (R)-IRED from Streptomyces kanamyceticus, was constructed and used to identify potential amino acids as targets for
Development of an R-selective amine oxidase with broad substrate specificity and high enantioselectivity
Heath, Rachel S.,Pontini, Marta,Bechi, Beatrice,Turner, Nicholas J.
, p. 996 - 1002 (2014/05/06)
Amine oxidases are useful bio-catalysts for the synthesis of enantiomerically pure 1°, 2° and 3° chiral amines. Enzymes in this class (e.g., MAO-N from Aspergillus niger) reported previously have been shown to be highly S selective. Herein we report the development of an enantiocomplementary R-selective amine oxidase based on 6-hydroxy-D-nicotine oxidase (6-HDNO) with broadened substrate scope and high enantioselectivity. The engineered 6-HDNO enzyme has been applied to the preparative deracemisation of a range of racemic amines to yield S-configured products, for example, (S)-nicotine, in high ee. Nicotine rush: An R-selective amine oxidase based on 6-hydroxy-D-nicotine oxidase (6-HDNO) with broadened substrate scope and high enantioselectivity has been developed. The engineered 6-HDNO enzyme is applied to the preparative deracemization of a range of racemic amines to yield S-configured products, for example, (S)-nicotine, in high ee.
Asymmetric synthesis of 2-arylpyrrolidines starting from γ-chloro N-(tert-butanesulfinyl)ketimines
Leemans, Erika,Mangelinckx, Sven,De Kimpe, Norbert
scheme or table, p. 3122 - 3124 (2010/09/04)
The enantioselective reductive cyclization of γ-chloro N-(tert-butanesulfinyl)ketimines towards the short and efficient synthesis of (S)- and (R)-2-arylpyrrolidines (ee >99%) is described for the first time by treatment with LiBEt3H and subsequ
