A new transition-metal-free amination of pyridine-2-sulfonyl chloride and related N-heterocycles using magnesium amides of type R2NMgCl·LiCl is reported. Additionally, the directed ortho-magnesiation of pyridine-2-sulfonamides using TMPMgCl·LiCl was investigated. Reaction of the magnesium intermediates with various electrophiles and subsequent amination using magnesium amides led to a range of 2,3-functionalized
Catalyst-Free Sulfonylation of (Hetero)aryl Iodides with Sodium Dithionite
作者:Yuewen Li、Tong Liu、Guanyinsheng Qiu、Jie Wu
DOI:10.1002/adsc.201801445
日期:2019.3.5
The commercially available and cheap sodium dithionite is used as the source of sulfonyl group for the synthesis of sulfones and sulfonamides from (hetero)aryl iodides under catalyst‐free conditions. During the reaction process, sodiumsulfinates generated in situ are the key intermediate, which can be further converted into diverse sulfones and sulfonamides. This transformation proceeds through a
Nickel-Catalyzed Intramolecular Desulfitative C—N Coupling: A Synthesis of Aromatic Amines
作者:Jiangjun Liu、Xiuwen Jia、Xuemeng Chen、Haotian Sun、Yue Li、Søren Kramer、Zhong Lian
DOI:10.1021/acs.joc.0c00009
日期:2020.4.17
intramolecular C—N coupling reaction via SO2 extrusion is presented. The use of a catalytic amount of BPh3 allows the transformation to take place under much milder conditions (60 °C) than previously reported C—N coupling reactions by CO or CO2 extrusion (160–180 °C). In addition, this method displays good functional group tolerance and versatility, as it can be applied to the synthesis of dialkyl aryl
One-pot synthesis of sulfonamides from methyl sulfinates using ultrasound
作者:José L. García Ruano、Alejandro Parra、Leyre Marzo、Francisco Yuste、Virginia M. Mastranzo
DOI:10.1016/j.tet.2011.02.060
日期:2011.4
Room temperature ultrasonic irradiation of neat mixtures of methyl sulfinates and primary or secondary amines (1.5 equiv) produced sulfinamides, which on m-CPBA oxidation (in dichloromethane) were converted into the corresponding sulfonamides. The two steps can be accomplished in one pot, in good overall yields, when using secondary amines, but primary amines give better sulfonamide yields when the peracid oxidation is effected on the purified sulfinamide. This constitutes a mild, efficient, and potentially scalable route to sulfonamides, which obviates the use of water sensitive, often lachrymatory sulfonyl chlorides and large reagent excesses. (C) 2011 Elsevier Ltd. All rights reserved.