Radical Enamination of Vinyl Azides: Direct Synthesis of N-Unprotected Enamines
摘要:
An electron-withdrawing-group-generable radical-induced enamination of vinyl azides is reported, which results in a variety of beta-functionalized N-unprotected enamines in a stereoselective manner. A plausible mechanism involving an unusual 1,3-H transfer of in situ generated iminyl radical intermediate was proposed on the basis of experimental results and DFT calculations.
Radical Enamination of Vinyl Azides: Direct Synthesis of N-Unprotected Enamines
摘要:
An electron-withdrawing-group-generable radical-induced enamination of vinyl azides is reported, which results in a variety of beta-functionalized N-unprotected enamines in a stereoselective manner. A plausible mechanism involving an unusual 1,3-H transfer of in situ generated iminyl radical intermediate was proposed on the basis of experimental results and DFT calculations.
Amine-catalyzed synthesis of N2-sulfonyl 1,2,3-triazole in water and the tunable N2-H 1,2,3-triazole synthesis in DMSO via metal-free enamine annulation
作者:Yanhui Guo、Yunyun Liu、Jie-Ping Wan
DOI:10.1016/j.cclet.2021.08.003
日期:2022.2
N2-H 1,2,3-triazoles via organocatalytic annulation of enaminone/enaminoester with sulfonylazide has been realized. The unconventional selectivity providing N2-sulfoyl 1,2,3-triazoles takes place in pure water, wherein the hydrogen bond effect between water and the intermediate resulting from enamine-azide corporation accounts for the novel reaction selectivity. On the other hand, the reactions conducted
2,3‐Dichloro‐5,6‐Dicyano‐1,4‐Benzoquinone (DDQ)‐Mediated Tandem Oxidative Coupling/Intramolecular Annulation/Dehydro‐Aromatization for the Synthesis of Polysubstituted and Fused Pyridines
作者:Dongping Cheng、Zhiteng Deng、Xianhang Yan、Mingliang Wang、Xiaoliang Xu、Jizhong Yan
DOI:10.1002/adsc.201900956
日期:2019.11.5
A DDQ‐mediated tandem reaction of 1,3‐diarylpropenes and β‐enaminoesters/4‐aminocoumarins is disclosed. It involves oxidative coupling, intramolecular annulation and dehydro‐aromatization reaction, which provides an efficient and mild method for the synthesis of polysubstituted and fused pyridines under metal‐free conditions.
Asymmetric Aza-Diels–Alder Reactions of in Situ Generated β,β-Disubstituted α,β-Unsaturated N–H Ketimines Catalyzed by Chiral Phosphoric Acids
作者:Shunlong He、Huanchao Gu、Yu-Peng He、Xiaoyu Yang
DOI:10.1021/acs.orglett.0c01994
日期:2020.7.17
A novel asymmetricsynthesis of dihydropyridinones with vicinal quaternary stereocenters has been realized by asymmetric aza-Diels–Alder reactions of 3-amido allylic alcohols with oxazolones enabled by chiral phosphoric acid catalysis. A series of aryl/alkyl- and alkyl/alkyl-disubstituted 3-amido allylic tertiary alcohols and 4-substituted oxazolones could be well tolerated in these reactions, producing
Solid-State Synthesis of β-Enamino
Ketones from Solid 1,3-Dicarbonyl Compounds and Ammonium
Salts or Amines
作者:Jing-Hua Li、Shi-Liang Xu、Cheng-Ping Li
DOI:10.1055/s-0028-1087914
日期:——
A facile amination of solid 1,3-dicarbonyl compounds with ammonium salts or amines in solid state has been achieved by mechanochemical grinding in the presence of KHSO4 and SiO2. Most of the reactions proceed smoothly at room temperature under solid-state conditions and give their corresponding β-imino derivatives in high yields. The method has the advantage of simple manipulation and mild conditions.
An efficient method for the synthesis of enaminones is described. The aldol-type addition of ketones to aromatic nitriles proceeded smoothly in the presence of a simple copper catalyst system (CuI–2,2′-bipyridine–NaOtBu) in N,N-dimethylformamide. Enaminones in satisfactory to excellent yields were produced using this technique.