使用铱催化的不对称氢化反应制备了几种手性磺酰基化合物。研究了乙烯基、烯丙基和高烯丙基砜的取代,无论烯烃相对于砜的位置如何,都保持了高对映选择性。二烷基取代获得了令人印象深刻的立体选择性,这通常是氢化中具有挑战性的底物。正如预期的那样,体积更大的 Z 底物比相应的 E 异构体氢化得更慢,并且对映选择性略低。
Electrosynthesis of (<i>E</i>)-Vinyl Sulfones Directly from Cinnamic Acids and Sodium Sulfinates via Decarboxylative Sulfono Functionalization
作者:Peng Qian、Meixiang Bi、Jihu Su、Zhenggen Zha、Zhiyong Wang
DOI:10.1021/acs.joc.6b00661
日期:2016.6.3
A variety of (E)-vinyl sulfones were constructed directly from cinnamic acids and sodium sulfinates with high regioselectivity at room temperature by virtue of an electrocatalytic oxidation. A radical intermediate was detected, and the corresponding mechanism was investigated.
The contra-thermodynamic isomerization of α- and β-substituted cinnamate derivatives catalyzed by the Cu(OAc)2/rac-BINAP complex under blue light irradiation is reported. The use of an oxazolidinone template, which favored the complexation of the copper catalyst to the substrate, allowed the E → Z isomerization of the catalytically formed chromophore under simple and robust reaction conditions in good
hydrazides depended to a great extent on the choice of a solvent and catalyst. In the presence of dimethylformamide (DMF), β-alkyl nitroalkenes more likely converted into electron-rich allyl nitro compounds, which reacted with sulfonyl hydrazides to afford allylsulfones with high regioselectivity. While in acetonitrile (CH3CN), vinyl sulfones were obtained directly via sulfonation of electron-deficient β-alkyl
Visible Light-Mediated Metal-Free Synthesis of Vinyl Sulfones from Aryl Sulfinates
作者:Andreas Uwe Meyer、Stefanie Jäger、Durga Prasad Hari、Burkhard König
DOI:10.1002/adsc.201500142
日期:2015.6.15
Visiblelight and eosin Y catalyze the synthesis of vinyl sulfones from aryl sulfinates and alkenes by a photoredox process. The reaction scope is broad in aryl sulfinates and alkenes and the general and simple procedure provides a metal‐free alternative for the synthesis of synthetically valuable vinyl sulfones.
Synthesis of Vinyl Sulfoxides Using Sulfinyl Chlorides and Olefins
作者:Xiancai Ding、Jianming Wen、Jianqiang Wang、Jun Yu、Jing-Hua Li
DOI:10.3184/174751915x14304098020793
日期:2015.5
synthesis of vinyl sulfoxides, using sulfinyl chlorides and olefins as starting materials and DBU as an HCl scavenger, has been developed. Vinyl sulfoxides were obtained from the ZnCl2 catalysed addition of sulfinyl chlorides to olefins followed by the elimination with DBU. However, the direct reaction of sulfinyl chlorides with olefins in the presence of DBU, usually leads to generation of vinyl sulfones