Palladium-catalysed aminosulfonylation of aryl-, alkenyl- and heteroaryl halides: scope of the three-component synthesis of N-aminosulfonamides
作者:Edward J. Emmett、Charlotte S. Richards-Taylor、Bao Nguyen、Alfonso Garcia-Rubia、Barry R. Hayter、Michael C. Willis
DOI:10.1039/c2ob07034k
日期:——
By using DABCO·(SO2)2, DABSO, as a solid bench-stable SO2-equivalent, the palladium-catalysed aminosulfonylation of aryl-, alkenyl- and heteroaryl halides has been achieved. N,N-Dialkylhydrazines are employed as the N-nucleophiles and provide N-aminosulfonamides as the products in good to excellent yields. The reactions are operationally simple to perform, requiring only a slight excess of SO2 (1.2–2.2 equiv.), and tolerate a variety of substituents on the halide coupling partner. Variation of the hydrazine component is also demonstrated. The use of N,N-dibenzylhydrazine as the N-nucleophile delivers N-aminosulfonamide products that can be converted into the corresponding primary sulfonamides using a high-yielding, telescoped, deprotection sequence. The ability to employ hydrazine·SO2 complexes as both the N-nucleophile and SO2 source is also illustrated.
作者:Charlotte S. Richards-Taylor、David C. Blakemore、Michael C. Willis
DOI:10.1039/c3sc52332b
日期:——
electrophilic coupling partner, such as a benzylic, allylic or alkyl halide, an electron-poor arene, or a cyclic epoxide, to provide the corresponding sulfone products in good to excellent yields. The mild reaction conditions and use of commercially available reaction components allows the easy preparation of a broad range of sulfones featuring a variety of functional groups. The process obviates the need
A palladium-catalyzed coupling reaction of aryl nonaflates, sulfur dioxide, and hydrazines
作者:Yuanyuan An、Hongguang Xia、Jie Wu
DOI:10.1039/c5ob02514a
日期:——
nonaflates, sulfurdioxide, and hydrazines is reported. This transformation proceeds in the presence of Pd(OAc)2/XantPhos, and TBAB in 1,4-dioxane at 80 °C, leading to the corresponding N-aminosulfonamides in moderate to good yields. The reaction scope has been demonstrated, and good functional tolerance is observed. A plausible mechanism is proposed through the insertion of sulfurdioxide.
A palladium-catalyzed reaction of aryl halides, potassium metabisulfite, and hydrazines
作者:Shengqing Ye、Jie Wu
DOI:10.1039/c2cc34957d
日期:——
Aryl N-aminosulfonamides could be easily produced via a palladium-catalyzed coupling of aryl halides, potassium metabisulfite, and hydrazines. Potassium metabisulfite is an excellent equivalent of sulfur dioxide in the reaction of palladium-catalyzed aminosulfonylation.
Metal-Free Aminosulfonylation of Aryldiazonium Tetrafluoroborates with DABCO⋅(SO<sub>2</sub>)<sub>2</sub>and Hydrazines
作者:Danqing Zheng、Yuanyuan An、Zhenhua Li、Jie Wu
DOI:10.1002/anie.201309851
日期:2014.2.24
The coupling of aryldiazoniumtetrafluoroborates, DABCO⋅(SO2)2, and hydrazines under metal‐free conditions leads to the formation of aryl N‐aminosulfonamides. The reaction proceeds smoothly at room temperature and shows broad functional‐group tolerance. A radical process is proposed for this transformation.