A highly enantioselectivearylation of 3-carboxamide oxoindoles with quinone monoimines is described. Various 3-aryl-3-carboxamide oxindoles with an all-carbon quaternary center were obtained in moderate to good yields (up to 99%) with moderate to good enantioselectivities (up to 98%) in the presence of a bifunctional thiourea-tertiary amine catalyst. The absolute configuration of one product was determined
Phenyliodine Bis(trifluoroacetate) Mediated Intramolecular Oxidative Coupling of Electron-Rich N-Phenyl Benzamides
作者:Wei Yu、Zhengsen Yu、Lijuan Ma
DOI:10.1055/s-0031-1290680
日期:2012.6
The intramolecularoxidative C–O coupling of N-(4-alkoxy-phenyl) and N-(4-acetamido-phenyl) benzamides was achieved under metal-free conditions by using phenyliodine bis(trifluoroacetate) as oxidant and TMSOTf as catalyst. The reactions afford benzoxazole products in high yields.
Synthesis of 5-substituted 2,3-dihydrobenzofurans in a one-pot oxidation/cyclization reaction
作者:Fabien Baragona、Thierry Lomberget、Christian Duchamp、Natali Henriques、Eugenio Lo Piccolo、Patrizia Diana、Alessandra Montalbano、Roland Barret
DOI:10.1016/j.tet.2011.09.020
日期:2011.11
Variously substituted 2,3-dihydrobenzofurans have been synthesized according :o a sequential one-pot oxidation/cyclization procedure between para-aminophenol derivatives and an azadiene. (C) 2011 Elsevier Ltd. All rights reserved.
Hydrohalogenation of N-acetyl(aroyl)-1,4-benzoquinone monoimines
作者:A. P. Avdeenko、S. A. Konovalova、O. N. Ludchenko、O. P. Ledeneva、A. V. Vakulenko
DOI:10.1134/s1070428011020102
日期:2011.2
New N-acetyl-1,4-benzoquinone monoimines alkyl-substituted in the quinoid ring were synthesized. The hydrohalogenation of N-acetyl(aroyl)-1,4-benzoquinone monoimines proceeds exclusively in keeping with the 1,4-addition. The hydrochlorination occurs along the ionic mechanism, in the hydrobromination grows the role of the radical mechanism.
Spectrophotometric and titrimetric determination of carboxylic acid anhydrides