Palladium-Catalyzed Intramolecular Sulfonamidation/Oxidation of Imines: Access to Multifunctional Benzimidazoles
作者:Shaomin Fu、Huanfeng Jiang、Yuanfu Deng、Wei Zeng
DOI:10.1002/adsc.201100370
日期:2011.10
O-Sulfonamidophenylimines undergo intramolecularsulfonamidation/oxidation to produce 1,2-disubstituted benzimidazoles upon treatment with palladium(II) chloride/(diacetoxyiodo)benzene and potassium carbonate at room temperature. The substituent scope at the 2-position of the benzimidazole can be extended to alkyl, aryl, alkenyl, acyl, and ester functional groups under mild conditions.
An intramolecular Cu-catalyzed asymmetric propargylic [4 + 2] cycloaddition of bis-N-nucleophile-functionalized propargylic esters has been realized in the support of a chiral tridentate N-ligand, (S,S)-Pybox-diOAc, leading to chiral tetrahydroisoindolo[2,1-a]quinoxalines in high yields and with good to excellent enantioselectivities. The reaction features high efficiency, simplicity, and broad substrate
在手性三齿 N-配体 ( S , S )-Pybox-diOAc 的支持下,实现了双-N-亲核试剂官能化的炔丙基酯的分子内 Cu 催化的不对称炔丙基 [4 + 2] 环加成反应,从而产生手性四氢异吲哚[2,1- a ]喹喔啉的收率高,对映选择性良好。该反应具有高效、简单和广泛的底物范围,从而为立体选择性获得原本难以合成的光学活性多环杂环骨架提供了强大而简洁的策略。
Electrochemical Cyclization of o-Aminyl Azobenzenes: Roles of Aldehydes in N–N Bond Cleavage
作者:Anni Li、Anna Gao、Kangjia Chen、Hongji Li
DOI:10.1021/acs.orglett.4c01828
日期:2024.8.2
molecules in synthetic chemistry. However, an efficient method for the cleavage of the N═N bond of azobenzenes, which is a key process for this transformation, is still lacking. We herein disclose an electrochemical reduction-induced cyclization of azobenzenes with aldehydes via N═N bond cleavage. This electrochemicalcyclization of azobenzenes proceeds well in the absence of any transition metals or external