三氟甲磺酸酐与2-氯吡啶共介串联活化、分子内芳香族亲电加成以及α-酰基磺酰甲基锍螺环中间体的1,2-磺酰基转移实现了2-烷基/芳基硫代苯并[ b ]噻吩1,1-的高效合成二氧化碳。失活的磺酰基通过原位攻击决定亲电加成的位点选择性,而随后的 S-迁移控制区域选择性。一些 2-甲硫基苯并[ b ]噻吩 1,1-二氧化物在固态及其溶液中表现出荧光特性。
Photo‐Mediated Decarboxylative Ketonization of Atropic Acids with Sulfonyl Hydrazides: Direct Access to
<i>β</i>
‐Ketosulfones
作者:Jie Chen、Zoe G. Allyson、Jing‐Rui Xin、Zhi Guan、Yan‐Hong He
DOI:10.1002/adsc.201901525
日期:2020.5.12
synthetically and biologically relevant β‐ketosulfones via a photo‐mediated decarboxylative ketonization of atropic acids was disclosed. The approach features metal‐free conditions, good functional group compatibility, readily available starting materials and the use of ubiquitous dioxygen as both oxygen source and oxidant. Furthermore, mechanistic studies reveal that the decarboxylative ketonization
Synthesis of Sulfones <i>via</i> Ru(II)-Catalyzed Sulfination of Boronic Acids
作者:Krista Gulbe、Ma̅ris Turks
DOI:10.1021/acs.joc.9b03403
日期:2020.4.17
Ruthenium(II) complexes catalyze the insertion of sulfur dioxide into (het)aryl and alkenyl boronic acids. The transmetalation–sulfination process proceeds with DABSO in the presence of 5 mol % RuCl2(PPh3)3 in methanol at 100 °C. The intermediate sulfinate salt can be quenched with various electrophiles such as alkyl halides, epoxides, Michael acceptors, and λ3-iodanes in moderate to good yields. The
Heterogeneous Carbon Nitrides Photocatalysis Multicomponent Hydrosulfonylation of Alkynes To Access β-Keto Sulfones with the Insertion of Sulfur Dioxide in Aerobic Aqueous Medium
Although hydrosulfonylation of alkynes is an ideal process to generate β-ketosulfones, such an approach is rarely implemented. Here we reported a facile and efficient graphitic carbon nitride (p-g-C3N4) photocatalyzed hydrosulfonylation of alkynes with the insertion of sulfur dioxide in aerobic conditions. Controlled experiments and ESR results indicated both the superoxide radicals and valence band
A mild, practical method to prepare α-sulfonyl and α-trifluoromethyl ketones from readily available enol acetates and sulfonyl chlorides has been developed using visible-lightphotoredoxcatalysis. The method could be used with a wide range of enol acetates and sulfonyl chlorides, and gave the desired products in satisfactory to excellent yields.