lariat ethers have been synthesized. These macrocycles and their derivatives proved to be efficient catalysts in the cyclopropanation of (E)-3-phenyl-2-(phenylsulfonyl)acrylonitrile performed with diethyl bromomalonate under mild phase transfer conditions. Among the catalysts tested, the macrocycle having methylα-d-galactopyranoside unit generated the highest asymmetric induction (80% ee). In the
Asymmetric cyclopropanation of conjugated cyanosulfones using a novel cupreine organocatalyst: rapid access to δ<sup>3</sup>-amino acids
作者:Lewis S. Aitken、Lisa E. Hammond、Rajkumar Sundaram、Kenneth Shankland、Geoffrey D. Brown、Alexander J. A. Cobb
DOI:10.1039/c5cc05158d
日期:——
A novel hydroquinine derived organocatalyst has been used to make cyclopropanes useful in the construction of δ3-amino acids.
一种新型的羟基喹啉衍生有机催化剂已被用于制备环丙烷,用于构建δ3-氨基酸。
Reactions of 3-methyl-2-oxopyrazolidinium ylides with phenylsulfonylacrylonitriles
作者:Yaşar Dürüst、Eda Sağırlı、Akın Sağırlı
DOI:10.1016/j.tet.2015.10.022
日期:2015.12
A series of methyl oxopyrazolidinium ylides was reacted with (E)-3-(2-hydroxyphenyl)-2-(phenyl-sulfonyl)acrylonitrile and 2-phenylsulfonyl acrylonitrile to give rise to (1R,2S,3S)-5-methyl-7-oxo-1,3-p-substituteddiphenyl-2-(phenylsulfonyl)-hexahydropyrazolo[1,2-a]pyrazole-2-carbonitriles through a sequential reaction accompanying methyl pyrazolone and o-quinone methide releases possibly instead of an anticipated cycloaddition process and 1,3-dipolar cycloaddition route. All the new products were identified by means of spectral/physical characteristics including X-ray diffraction data and HRMS measurements. In addition, a plausible mechanism is proposed for hydroxyphenyl substituted acrylonitrile case. (C) 2015 Elsevier Ltd. All rights reserved.
Na2CaP2O7, a new catalyst for the synthesis of unsaturated arylsulfones
The synthetic diphosphate Na2CaP2O7 is a new basic catalyst for the synthesis of unsaturated arylsulfones. The condensation was carried out under mild conditions at room temperature in methanol or ethanol. The optimum of the catalyst's activity is reached when water is added, leading to good yields. (C) 2003 Elsevier Science Ltd. All rights reserved.
A GENERAL METHOD TO POLYSUBSTITUTED 4-CYANO-4-PHENYLSULFONYLBUTYRIC ESTERS
作者:Zongbao Zhao、Yu Ding、Gang Zhao
DOI:10.1081/scc-100104457
日期:2001.1.1
Polysubstituted 4-cyano-4-phenylsulfonylbutyric esters are prepared by the addition of bromoacetate to 1-cyano-1-phenylsulfonyl alkenes mediated by Zn/Cp2TiCl2(cat.) at room temperature in good to high yield.