33237-91-1Relevant academic research and scientific papers
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)
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.
Nucleophilic Substitution Reactions of Indan-2-yl Arenesulfonates with Anilines in Methanol
Lee, Ikchoon,Lee, Young Sook,Huh, Chul,Lee, Hai Whang,Lee, Byung Choon
, p. 2415 - 2418 (2007/10/02)
The nucleophilic substitution reactions of (Y)-indan-2-yl (Z)-arenesulfonates with (X)-anilines in methanol at 55.0 deg C are reported.Sign reversals in all three second-order cross-interaction constants, ρXY, ρYZ and ρXZ, are observed at non-interaction points Z = -0.11 (ρXY = 0), X = -0.02 (ρYZ = 0) and Y = 0.43 (ρXZ = 0) respectively, which have been ascribed to an unusually large third-order cross-interaction constant, ρXYZ = -0.53, for the reaction series.An SN2 transition state with a tilted, parallel stacked and displaced structure of the three benzene rings in the nucleophile (X), substrate (Y) and leaving group (Z) is proposed to rationalize the strong three-body coupling manifested by the large ρXYZ value.
