Three-Component Cascade Annulation of β-Ketothioamides Promoted by CF<sub>3</sub>CH<sub>2</sub>OH: A Regioselective Synthesis of Tetrasubstituted Thiophenes
作者:Li-Rong Wen、Tao He、Ming-Chao Lan、Ming Li
DOI:10.1021/jo401397d
日期:2013.11.1
A rapid and highly efficient method for the regioselective synthesis of thiophene derivatives has been developed by annulation of β-ketothioamides with arylglyoxals and 5,5-dimethyl-1,3-cyclohexanedione in CF3CH2OH within 15 min. The present synthesis has several desirable features, such as high regioselectivity, a concise one-pot protocol, short reaction time, and easy purification. This methodology
Modulating the Reactivity of Functionalized <i>N</i>,<i>S</i>-Ketene Acetal in MCR: Selective Synthesis of Tetrahydropyridines and Thiochromeno[2,3-<i>b</i>]pyridines via DABCO-Catalyzed Tandem Annulation
作者:Li-Rong Wen、Yong-Jie Shi、Guang-Yuan Liu、Ming Li
DOI:10.1021/jo202665q
日期:2012.5.4
An efficient and straightforward three-component synthetic protocol was developed to synthesize 1,2,3,4-tetrahydropyridine derivatives or thiochromeno[2,3-b]pyridine derivatives from beta-aroylthioacetanilides or beta-(2-haloaroyl)thioacetanilides, aldehydes, and aroyl acetonitriles via DABCO-catalyzed tandem [3 + 2 + 1] annulation and SNAr reaction. This synthetic approach has the prominent features of high chemo-, stereo- (or enantio-), and unusual regioselectivity. In the domino processes, at least seven reactive sites were involved, and up to three covalent bonds and one functionalized pyridine ring were generated. This facile and efficient reaction is a quite general for the preparation of tetrahydropyridine derivatives or thiochromeno[2,3-b]pyridine derivatives.