51713-72-5Relevant articles and documents
CATALYTIC SYSTEMS FOR STEREOSELECTIVE SYNTHESIS OF CHIRAL AMINES BY ENANTIODIVERGENT RADICAL C-H AMINATION
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Paragraph 0201; 0242-0243; 0250, (2020/11/27)
In one aspect, the disclosure relates to a mode of asymmetric induction in radical processes based on sequential combination of enantiodifferentiative H-atom abstraction and stereoretentive radical substitution. Also disclosed is an asymmetric system for stereoselective synthesis of strained 5-membered cyclic sulfamides via radical 1,5-C—H amination of sulfamoyl azides. The disclosed metalloradical system can control the degree and sense of asymmetric induction in the catalytic radical C—H amination in a systematic manner. The disclosed system is applicable to a broad scope of substrates with different types of C(sp3)-H bonds and exhibits reactivity and selectivity, providing access to both enantiomers of useful 5-membered cyclic sulfamides in a highly enantioenriched form. Also disclosed are catalysts useful in these processes. This abstract is intended as a scanning tool for purposes of searching in the particular art and is not intended to be limiting of the present disclosure.
Synthesis of Symmetric and Unsymmetric Secondary Amines from the Ligand-Promoted Ruthenium-Catalyzed Deaminative Coupling Reaction of Primary Amines
Arachchige, Pandula T. Kirinde,Lee, Hanbin,Yi, Chae S.
, p. 4932 - 4947 (2018/05/08)
The catalytic system generated in situ from the tetranuclear Ru-H complex with a catechol ligand (1/L1) was found to be effective for the direct deaminative coupling of two primary amines to form secondary amines. The catalyst 1/L1 was highly chemoselective for promoting the coupling of two different primary amines to afford unsymmetric secondary amines. The analogous coupling of aniline with primary amines formed aryl-substituted secondary amines. The treatment of aniline-d7 with 4-methoxybenzylamine led to the coupling product with significant deuterium incorporation on CH2 (18% D). The most pronounced carbon isotope effect was observed on the α-carbon of the product isolated from the coupling reaction of 4-methoxybenzylamine (C(1) = 1.015(2)). A Hammett plot was constructed from measuring the rates of the coupling reaction of 4-methoxyaniline with a series of para-substituted benzylamines 4-X-C6H4CH2NH2 (X = OMe, Me, H, F, CF3) (ρ = -0.79 ± 0.1). A plausible mechanistic scheme has been proposed for the coupling reaction on the basis of these results. The catalytic coupling method provides an operationally simple and chemoselective synthesis of secondary amine products without using any reactive reagents or forming wasteful byproducts.
Tandem synthesis of amides and secondary amines from esters with primary amines under solvent-free conditions
Lee, Jeongbin,Muthaiah, Senthilkumar,Hong, Soon Hyeok
, p. 2653 - 2660 (2014/09/17)
An iridium(III)-catalyzed tandem synthesis of amides and amines from esters under solvent-free conditions is described. A commercially available iridium(III) complex, [Cp*IrCl2]2, with sodium acetate showed the best activity for the synthesis of amides and secondary amines. The amide was formed by ester-amide exchange which generates an alcohol in situ which is subsequently transformed to a secondary amine via hydrogen autotransfer. This synthetic protocol with high atom economy generates water as the sole by-product and can afford amides and amines from various esters in a one-pot reaction, expanding the synthetic versatility of ester transformations.
