[EN] 1,2,4-SUBSTITUERTE 1,2,3,4-TETRAHYDRO-AND 1,2 DIHYDRO-QUINOLINE AND 1,2,3,4-TETRAHYDRO-QUINOXALINE DERIVATIVES AS CETP INHIBITORS FOR THE TREATMENT OF ATHEROSCLEROSIS AND OBESITY [FR] DERIVES DE 1,2,3,4-TETRAHYDRO- ET 1,2 DIHYDRO-QUINOLEINE ET 1,2,3,4-TETRAHYDRO-QUINOXALINE 1,2,4-SUBSTITUES, UTILES COMME INHIBITEURS DE CETP POUR LE TRAITEMENT DE L'ATHEROSCLEROSE ET DE L'OBESITE
The search for efficient molecular hydrogenprecursors and their catalytic exploration is necessary for the evolution of catalytic transfer hydrogenation. Methyl formate (MF) having high hydrogen content still remains unexplored for such transformations. Herein, we disclosed a bifunctional Ir(III)-complex catalyzed chemoselective TH protocol for N-heteroarenes and azoarenes using MF. A variety of substrates
The combination of [Cp*IrCl2](2) with N-(2-aminoethyl)-4-(trifluoromethyl)benzenesulfonamide constitutes an efficient catalyst for selective transfer hydrogenation of a variety of quinoxalines in water with HCOONa as the hydrogen source, affording the corresponding tetrahydroquinoxalines in good to excellent yields. The catalyst is air-stable, and the reduction could be performed without nitrogen protection. The aqueous phase reduction is shown to be highly pH-dependent, with acidic pH leading to better results. There exits a pH window for optimum rate, and the use of HOAc/NaOAc buffer solution is essential for maintaining a stable pH during the reaction. (C) 2011 Elsevier Ltd. All rights reserved.