5183-78-8Relevant articles and documents
N-Aroylsulfonamide-Photofragmentation (ASAP)-A Versatile Route to Biaryls
Wessig, Pablo,Krebs, Saskia
supporting information, p. 6367 - 6374 (2021/09/29)
The photochemical fragmentation of N-aroylsulfonamides 9 (ASAP) is a powerful method for the preparation of various biaryls. Compounds 9 are easily accessible in two steps from amines by treatment with arenesulfonyl chlorides and aroyl chlorides. Many of these compounds were prepared for the first time. The irradiation takes place in a previously developed continuous-flow reactor using inexpensive UVB or UVC fluorescent lamps. Isocyanates and sulphur dioxide are formed as the only by-products. The ASAP tolerates a variety of functional groups and is even suited for the preparation of phenylnaphthalenes and terphenyls. The ASAP mechanism was elucidated by interaction of photophysical and quantum chemical (DFT) methods and revealed a spirocyclic biradical as key intermediate.
Structurally Diverse Synthesis of Five-, Six-, and Seven-Membered Benzosultams through Electrochemical Cyclization
Liu, Aiyun,Guo, Tiantian,Zhang, Shuangshuang,Yang, Han,Zhang, Qi,Chai, Yonghai,Zhang, Shengyong
supporting information, p. 6326 - 6331 (2021/08/23)
We have developed a metal- and oxidant-free approach to structurally diverse synthesis of benzosultams from aryl sulfonamides through an electrochemical cyclization. Upon variation of the ortho substituent on aryl sulfonamides, five-, six-, and seven-memb
Electrochemical C?H Amidation of Heteroarenes with N-Alkyl Sulfonamides in Aqueous Medium
Zhang, Yan,Lin, Zhipeng,Ackermann, Lutz
supporting information, p. 242 - 246 (2020/11/30)
The construction of C?N bonds by free radical reactions represents a powerful synthetic approach for direct C?H amidations of arenes or heteroarenes. Developing efficient and more environmentally friendly synthetic methods for C?H amidation reactions remains highly desirable. Herein, metal-free electrochemical oxidative dehydrogenative C?H amidations of heteroarenes with N-alkylsulfonamides have been accomplished. The catalyst- and chemical-oxidant-free C?H amidation features an ample scope and employs electricity as the green and sole oxidant. A variety of heteroarenes, including indoles, pyrroles, benzofuran and benzothiophene, thereby underwent this C(sp2)?H nitrogenation. Cyclic voltammetry studies and control experiments provided evidence for nitrogen-centered radicals being directly generated under metal-free electrocatalysis.
Recyclable covalent triazine framework-supported iridium catalyst for the N-methylation of amines with methanol in the presence of carbonate
Liu, Peng,Yang, Jiazhi,Ai, Yao,Hao, Shushu,Chen, Xiaozhong,Li, Feng
, p. 281 - 290 (2021/03/26)
An iridium complex Cp*Ir@CTF, which is synthesized by the coordinative immobilization of [Cp*IrCl2]2 on a functionalized covalent triazine framework (CTF), was found to be a general and highly efficient catalyst for the N-methylation of amines with methanol in the presence of carbonate. Under environmentally benign conditions, a variety of desirable products were obtained in high yields with complete selectivities and functional group friendliness. Furthermore, the synthesized catalyst could be recycled by simple filtration without obvious loss of catalytic activity after sixth cycle. Notably, this research exhibited the potential of covalent triazine framework-supported transition metal catalysts for hydrogen autotransfer process.
N-Methylation of Amines with Methanol in the Presence of Carbonate Salt Catalyzed by a Metal-Ligand Bifunctional Ruthenium Catalyst [(p-cymene)Ru(2,2′-bpyO)(H2O)]
Liu, Peng,Tung, Nguyen Thanh,Xu, Xiangchao,Yang, Jiazhi,Li, Feng
, p. 2621 - 2631 (2021/02/27)
A ruthenium complex [(p-cymene)Ru(2,2′-bpyO)(H2O)] was found to be a general and efficient catalyst for the N-methylation of amines with methanol in the presence of carbonate salt. Moreover, a series of sensitive substituents, such as nitro, ester, cyano, and vinyl groups, were tolerated under present conditions. It was confirmed that OH units in the ligand are crucial for the catalytic activity. Notably, this research exhibited the potential of metal-ligand bifunctional ruthenium catalysts for the hydrogen autotransfer process.
Boronic Acid Pairs for Sequential Bioconjugation
Ball, Zachary T.,Ding, Yuxuan,Miller, Mary K.,Swierczynski, Michael J.
supporting information, p. 5334 - 5338 (2021/07/26)
Boronic acids can play diverse roles when applied in biological environments, and employing boronic acid structures in tandem could provide new tools for multifunctional probes. This Letter describes a pair of boronic acid functional groups, 2-nitro-arylboronic acid (NAB) and (E)-alkenylboronic acid (EAB), that enable sequential cross-coupling through stepwise nickel- and copper-catalyzed processes. The selective coupling of NAB groups enables the preparation of stapled peptides, protein-protein conjugates, and other bioconjugates.
Copper-catalyzed oxidative methylation of sulfonamides by dicumyl peroxide
Che, Shiying,Zhu, Qiao,Luo, Zhenghong,Lian, Yan,Zhao, Zijian
, p. 935 - 942 (2021/01/05)
A novel and facile copper-catalyzed methylation of sulfonamides was herein demonstrated. The practical transformation took place readily under the oxidative conditions, and N-methyl amides (23 examples) were successfully furnished in high efficiency (up to 90% yields). Dicumyl peroxide was considered to act not only as the oxidant in the system, but also methyl donor for the methylation protocol.
Method for synthesizing N-methyl sulfonamide in water
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Paragraph 0025-0029; 0115; 0116, (2020/03/12)
The invention discloses a method N - for synthesizing,methylsulfamide in water, by using a transition metal iridium catalyst to catalyze N - methylation reaction. by using a non-toxic and harmless water as a solvent, to avoid using the organic agent; to react only as a byproduct, without an environmental hazard; reaction temperature with respect to the previous strip more mild; and have a wide application prospect; with high selectivity, reaction atomic economy.
N-Methylation of Amines with Methanol in Aqueous Solution Catalyzed by a Water-Soluble Metal-Ligand Bifunctional Dinuclear Iridium Catalyst
Han, Xingyou,Li, Feng,Liu, Peng,Meng, Chong,Tung, Nguyen Thanh
, p. 5815 - 5824 (2020/05/26)
The N-methylation of amines with methanol in aqueous solution was proposed and accomplished by using a water-soluble metal-ligand bifunctional dinuclear iridium catalyst. In the presence of [(Cp*IrCl)2(thbpym)][Cl]2 (1 mol %), a range of desirable products were obtained in high yields under environmentally benign conditions. Notably, this research exhibited the potential of transition metal-catalyzed activation of methanol as a C1 source for the construction of the C-N bond in aqueous solution.
Efficient and Practical Synthesis of Sulfonamides Utilizing SO2 Gas Generated on Demand
Chung Leung, Gulice Yiu,Ramalingam, Balamurugan,Loh, Gabriel,Chen, Anqi
, p. 546 - 554 (2020/04/22)
A simple and practical protocol was developed for the synthesis of sulfonamides by reacting organometallic reagents with SO2 gas generated on demand. SO2 was generated from readily available reagents safely in a highly contained and controlled fashion. The protocol allows the synthesis of sulfonamides without using either atom-inefficient SO2 surrogates or a SO2 cylinder that requires stringent storage regulations in the laboratory. The protocol was successfully applied to the synthesis of sildenafil.
