nitroarenes. The important features are the introduction of N-acetoxyacetamide as a new directing group, redox-neutral annulation, an additive-free approach, wide functional group tolerance, an intramolecular version, and a one-pot reaction of nitroarenes. The method was further extended to the synthesis of potent higher analogues of indole, viz., pyrrolo[3,2-f]indoles and dibenzo[a,c]carbazoles. In addition
N-乙酰氧基乙酰苯胺的一般和有效的铑催化氧化还原中性环化,容易从硝基芳烃中获得,与炔烃已经完成,用于合成取代的吲哚衍生物。从各种取代的N-乙酰氧基乙酰苯胺和对称/不对称炔烃中获得了范围广泛的取代 2,3-二芳基吲哚,产率从良好到优异。所开发的方法成功地与N-乙酰氧基乙酰苯胺的合成相结合,用于从硝基芳烃中有效地一锅法合成吲哚。重要的特点是引入了N-乙酰氧基乙酰胺作为新的导向基团,氧化还原中性环化,无添加剂方法,广泛的官能团耐受性,分子内形式和硝基芳烃的一锅反应。该方法进一步扩展到合成有效的高级吲哚类似物,即。、吡咯并[3,2- f ]吲哚和二苯并[ a , c ]咔唑。此外,基于潜在芳基-Rh中间体的分离和化学计量研究,提出了一种合理的机制。
Anionic Hetero[3,3] and [3,5] Rearrangements of Hydroxylamine Derivatives Accompanied with N-O Bond Cleavage
Aromatic and aliphatic N,O-divinylhydroxylamine systems generated in situ from hydroxylamine derivatives smoothly undergo [3,3] rearrangement. The base-catalyzed formation and rearrangement of enolates or dienolates of N-aryl-O-acylhydroxylamines, N,O- diacylhydroxylamines and N-acylhydroxylamine-O-carbamates result in C-C or C-N bond formation with cleavage of the N -O bond.
Synthesis of N,O-Diacetylated N-Arylhydroxylamines by Reduction of nitroaromatics with Zinc and Acetic Anhydride†
作者:Byeong Hyo Kim、Young Moo Jun、Seung Won Suh、Woonphil Baik、Byung Min Lee
DOI:10.1039/a705670b
日期:——
Reduction of nitroaromatic compounds with zinc and acetic anhydride in dichloromethane gave N,O-diacetylated N-arylhydroxylamines in good yields under mild conditions.
Catalyst-free generation of acyl radicals induced by visible light in water to construct C–N bonds
作者:Maogang Ran、Jiaxin He、Boyu Yan、Wenbo Liu、Yi Li、Yunfen Fu、Chao-Jun Li、Qiuli Yao
DOI:10.1039/d0ob02364g
日期:——
for the direct generation of acyl radicals fromα-diketones, and its selective conversion of nitrosoarenes to hydroxyamides or amides with AcOH or NaCl as an additive. The reaction was carried out under mild conditions in water with purple LEDs as the light source. A broad scope of substrates was demonstrated. Mechanistic experiments indicate that α-diketones cleave to give acyl radicals, with hydroxyamides
Anionic [3,3]-sigmatropic rearrangement of N-phenyl-O-acylhydroxylamines to o-aminophenylcetic acids.
作者:Yasuyuki Endo、Shoji Hizatate、Koichi Shudo
DOI:10.1016/0040-4039(91)85091-i
日期:1991.6
N-Phenyl-O-acylhydroxylamines rearrange under basic conditions to afford o-aminophenylacetic acids. The rearrangement can be rationalized in terms of [3,3]-sigmatropicshifts of an enolized N-phenyl-O-acylhydroxyl-amine.