385793-53-3Relevant academic research and scientific papers
CHIRAL CATALYST AND METHOD FOR ASYMMETRIC REDUCTION OF AN IMINE
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Paragraph 00116; 00117, (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.
Asymmetric Imine Hydroboration Catalyzed by Chiral Diazaphospholenes
Adams, Matt R.,Tien, Chieh-Hung,McDonald, Robert,Speed, Alexander W. H.
supporting information, p. 16660 - 16663 (2017/12/13)
The first use of diazaphospholenes as chiral catalysts has been demonstrated with enantioselective imine hydroboration. A chiral diazaphospholene prepared in a simple three-step synthesis from commercial materials has been shown to achieve the highest enantioselectivity for the hydroboration of alkyl imines with pinacolborane reported to date. Enantiomer ratios of up to 88:12 were obtained with low (2 mol %) catalyst loadings. Twenty examples of asymmetric reduction employing this main-group catalysis protocol, including the synthesis of the pharmaceuticals ent-rasagiline and fendiline, are shown.
Scope of the organocatalysed asymmetric reductive amination of ketones with trichlorosilane
Gautier, Franois-Moana,Jones, Simon,Li, Xianfu,Martin, Stephen J.
experimental part, p. 7860 - 7868 (2011/12/02)
A highly active organocatalyst has been shown to affect the asymmetric reductive amination of ketones producing both aromatic and aliphatic amines. At 1 mol% catalyst loading, a series of structurally diverse chiral amines were quickly and economically prepared with good enantioselectivity and generally useful yield. The efficient synthesis of the calcimimetic (+)-NPS R-568 (67%, 89% ee) demonstrated the synthetic applicability of this methodology.
A chiral "roofed" cis-diamine-Ru(II) complex: An efficient catalyst for asymmetric transfer hydrogenation of ketimines
Matsunaga, Hirofumi,Nakanishi, Kyoko,Nakajima, Makoto,Kunieda, Takehisa,Ishizuka, Tadao
experimental part, p. 617 - 622 (2009/06/18)
Highly enantioselective transfer hydrogenation of ketimines to the corresponding chiral amines was achieved with the chiral Ru(II) complex, prepared from the conformationally rigid and sterically bulky "roofed" cis-1,2-diamine.
Lithiated carbamates: Chiral carbenoids for iterative homologation of boranes and boronic esters
Stymiest, Jake L.,Dutheuil, Guillaume,Mahmood, Adeem,Aggarwal, Varinder K.
, p. 7491 - 7494 (2008/09/17)
(Chemical Equation Presented) Take your pick: Either enantiomer of either diastereomer of substrates bearing adjacent stereogenic centers is accessible through reaction of an (R)- or (S)-lithiated carbamate with an (R)- or (S)-boronic ester (see scheme; pin = pinacolate, OCb = substituted carbamate).
