I<sub>2</sub>-Promoted [4 + 2] cycloaddition of <i>in situ</i> generated azoalkenes with enaminones: facile and efficient synthesis of 1,4-dihydropyridazines and pyridazines
作者:Jiajun Feng、Tiantong He、Yuxing Xie、Yang Yu、Jonathan B. Baell、Fei Huang
DOI:10.1039/d0ob01958e
日期:——
A facile and efficient strategy for the synthesis of 1,4-dihydropyridazines and pyridazines through I2-promoted [4 + 2] cycloaddition of in situ generated azoalkenes with enaminones has been developed. The switch in selectivity is attributed to the judicious choice of different reaction temperatures. The key features of this work include controllable and selective synthesis, good functional group tolerance
已经开发了一种通过 I 2 -促进的 [4 + 2]原位生成的偶氮烯烃与烯胺酮环加成来合成 1,4-二氢哒嗪和哒嗪的简便有效的策略。选择性的转换归因于对不同反应温度的明智选择。这项工作的主要特点包括可控和选择性合成、良好的官能团耐受性、良好的反应收率、无金属/碱基条件以及一锅法的适用性。
Copper-Catalyzed One-Pot Synthesis of N-Sulfonyl Amidines from Sulfonyl Hydrazine, Terminal Alkynes and Sulfonyl Azides
作者:Yu Zhao、Zitong Zhou、Man Chen、Weiguang Yang
DOI:10.3390/molecules26123700
日期:——
amidines are developed from a Cu-catalyzed three-component reaction from sulfonyl hydrazines, terminal alkynes and sulfonylazides in toluene at room temperature. Particularly, the intermediate N-sulfonylketenimines was generated via a CuAAC/ring-opening procedure and took a nucleophilic addition with the weak nucleophile sulfonyl hydrazines. In addition, the stability of the product was tested by a HNMR
A novel palladium(0)‐catalyzed intermolecular coupling reaction of 2‐gem‐dibromovinylanilines and N‐tosylhydrazones was reported to construct 2‐(1‐phenylvinyl)‐indoles efficiently. The indole bearing 1, 1‐disubstituted alkenes were obtained in one step with short reaction time, in high yields and broad substrate scope. The formed indole derivates could be easily transformed into much more valuable
Pd-catalyzed oxidative cross-coupling of N-tosylhydrazones with arylboronic acids
作者:Xia Zhao、Jing Jing、Kui Lu、Yan Zhang、Jianbo Wang
DOI:10.1039/b925590g
日期:——
The Pd-catalyzed reaction of N-tosylhydrazones and arylboronic acids provides olefin derivatives. This oxidative cross-coupling is suggested to proceed through a migratory insertion process of a Pd carbene intermediate.
development of the Ir(III)-catalyzed direct C-H amidation of arenes and alkenes using acyl azides as the nitrogen source. This procedure utilizes an in situ generated cationic half-sandwich iridium complex as a catalyst. The reaction takes place under very mild conditions, and a broad range of sp(2) C-H bonds of chelate group-containing arenes and olefins are smoothly amidated with acyl azides without the intervention