Iodine was found to be an efficient catalyst for the imino Diels-Alder reaction of N-arylimine with enol ethers to provide tetrahydroquinolines in good yields. The influence of the loading of iodine, reaction solvent, the structure of imine and enol ethers was studied. One pot synthesis of tetrahydroquinolines from aldehyde, aniline and enol ethers catalyzed by iodine was also applicable and provided tetrahydroquinolines in comparable yields. Mild reaction conditions, facile experimental procedure, low price of iodine and good yield of products render this new method attractive for practical synthesis of many tetrahydroquinoline derivatives.
Iodine was found to be an efficient catalyst for the one pot synthesis of α-amino phosphonate from aldehydes, anilines and diethyl phosphite. The influences of the iodine loading, reaction solvent, the structure of aldehyde and aniline on the reaction were studied.
The reaction of methyl α-diazoacetoacetate with enamines catalyzed by dirhodium and copper complexes un-derwent formal 1,3-dipolar addition to give 5-amino-4,5-dihydrofurans in moderate yields. The reaction was sug-gested to proceed via a nucleophilic addition of enamines to metal-carbenes and a subsequent intramolecular cycli-zation of the resulting zwitterionic intermediates.
Antidepressant duloxetine (1) was prepared via asymmetric transfer hydrogenation of 3-(dimethylamino)-1-(thiophen-2- yl)propan-1-one (3). The Ru(Ⅱ), Rh(Ⅲ) and Ir(Ⅲ) complexes of several chiral ligands were examined as the catalyst and (S,S)-N-tosyl-1,2-diphenyl ethylenediamine (TsDPEN)-Ru(Ⅱ) complex was found to provide good yield and excellent enantioselectivity. 2007 Ming Yan. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.