Exploring the ring-opening reactions of imidazo[1,5-a]quinolines for the synthesis of imides under photochemical conditions

Ya Peng; Cheng-Tao Feng; Yu-Qing Li; Feng-Xiang Chen; Kun Xu

doi:10.1039/c9ob01227c

Ag2O-promoted ring-opening reactions of cyclopropenones with oximes

Organic & Biomolecular Chemistry ◽

10.1039/d0ob00601g ◽

2020 ◽

Vol 18 (30) ◽

pp. 5822-5825

Author(s):

Ye-Fei Yang ◽

Xiao-Bo Huang ◽

Wen-Xia Gao ◽

Yun-Bing Zhou ◽

Miao-Chang Liu ◽

...

Keyword(s):

Ring Opening ◽

Direct Route ◽

Ring Opening Reactions

We disclosed an Ag2O-promoted unprecedented ring-opening rearrangement of cyclopropenones with oximes, providing a direct route to 1,3-oxazinones.

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Catalyst Free, Nitromethane Assisted Facile Ring Opening of Epoxide with Less Reactive Aromatic Amines

10.26434/chemrxiv.12022908 ◽

2020 ◽

Author(s):

Sumit Kumar ◽

Meenakshi Bansal ◽

Charu Upadhyay ◽

Maria Grishina ◽

Vladimir Potemkin ◽

...

Keyword(s):

Aromatic Amines ◽

Ring Opening ◽

Spectroscopic Studies ◽

Bioactive Scaffolds ◽

Chemistry Research ◽

Ring Opening Reactions ◽

Ring Opening Of Epoxide ◽

Sterically Hindered ◽

First Time ◽

Nucleophilic Ring Opening

Nucleophilic ring opening reactions of epoxides with aromatic amines are in the forefront of the synthetic organic chemistry research to build new bioactive scaffolds. Here, a convenient, green and highly efficient regioselective ring opening of sterically hindered (2R,3S)-3-(N-Boc-amino)-1-oxirane-4-phenylbutane with various poorly reactive aromatic amines are accomplished under microwave irradiation in nitromethane. All the reactions effectively implemented for various aromatic amines involves reuse of nitromethane that supports its dual role as a solvent and catalyst. The corresponding new β-alcohol analogs of hydroxyethylamine (HEA) are isolated in 41-98% yields. The reactions proceed under mild conditions for a broad range of less reactive and sterically hindered aromatic amines. Proton NMR and UV-visible spectroscopic studies suggest that the nucleophilicity of amines is influenced by nitromethane, which is substantiated by the extensive computational studies. Overall, this methodology elucidates the first time use of nitromethane as a solvent for the ring opening reactions under microwave conditions involving equimolar ratio of epoxide and aromatic amine without any catalyst, facile ring opening of complex epoxide by less reactive aromatic amines, low reaction time, less energy consumption, recycling of the solvent and simple workup procedures.

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Iridium-catalyzed asymmetric ring-opening reactions of oxabicyclic alkenes with secondary amine nucleophiles

Beilstein Journal of Organic Chemistry ◽

10.3762/bjoc.5.53 ◽

2009 ◽

Vol 5 ◽

Cited By ~ 17

Author(s):

Dingqiao Yang ◽

Ping Hu ◽

Yuhua Long ◽

Yujuan Wu ◽

Heping Zeng ◽

...

Keyword(s):

Secondary Amine ◽

Ring Opening ◽

Secondary Amines ◽

X Ray ◽

X Ray Crystallography ◽

Ring Opening Reactions ◽

Oxabicyclic Alkenes ◽

First Time ◽

Asymmetric Ring Opening

Iridium-catalyzed asymmetric ring-opening reactions of oxabicyclic alkenes with various aliphatic and aromatic secondary amines are reported for the first time. The reaction gave the corresponding trans-1,2-dihydronaphthalenol derivatives in good yields with moderate enantioselectivities in the presence of 2.5 mol % [Ir(COD)Cl]2 and 5 mol % bisphosphine ligand (S)-p-Tol-BINAP. The trans-configuration of 3f was confirmed by X-ray crystallography.

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Catalyst Free, Nitromethane Assisted Facile Ring Opening of Epoxide with Less Reactive Aromatic Amines

10.26434/chemrxiv.12022908.v1 ◽

2020 ◽

Author(s):

Sumit Kumar ◽

Meenakshi Bansal ◽

Charu Upadhyay ◽

Maria Grishina ◽

Vladimir Potemkin ◽

...

Keyword(s):

Aromatic Amines ◽

Ring Opening ◽

Spectroscopic Studies ◽

Bioactive Scaffolds ◽

Chemistry Research ◽

Ring Opening Reactions ◽

Ring Opening Of Epoxide ◽

Sterically Hindered ◽

First Time ◽

Nucleophilic Ring Opening

Nucleophilic ring opening reactions of epoxides with aromatic amines are in the forefront of the synthetic organic chemistry research to build new bioactive scaffolds. Here, a convenient, green and highly efficient regioselective ring opening of sterically hindered (2R,3S)-3-(N-Boc-amino)-1-oxirane-4-phenylbutane with various poorly reactive aromatic amines are accomplished under microwave irradiation in nitromethane. All the reactions effectively implemented for various aromatic amines involves reuse of nitromethane that supports its dual role as a solvent and catalyst. The corresponding new β-alcohol analogs of hydroxyethylamine (HEA) are isolated in 41-98% yields. The reactions proceed under mild conditions for a broad range of less reactive and sterically hindered aromatic amines. Proton NMR and UV-visible spectroscopic studies suggest that the nucleophilicity of amines is influenced by nitromethane, which is substantiated by the extensive computational studies. Overall, this methodology elucidates the first time use of nitromethane as a solvent for the ring opening reactions under microwave conditions involving equimolar ratio of epoxide and aromatic amine without any catalyst, facile ring opening of complex epoxide by less reactive aromatic amines, low reaction time, less energy consumption, recycling of the solvent and simple workup procedures.

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ChemInform Abstract: Ring-Opening Reactions of Difluoro(methylene)cyclopropanes with Halogens and Amines.

ChemInform ◽

10.1002/chin.200912060 ◽

2009 ◽

Vol 40 (12) ◽

Author(s):

Xiao-Chun Hang ◽

Qing-Yun Chen ◽

Ji-Chang Xiao

Keyword(s):

Ring Opening ◽

Ring Opening Reactions

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Substituent Effects in Mechanochemical Allowed and Forbidden Cyclobutene Ring-Opening Reactions

Journal of the American Chemical Society ◽

10.1021/jacs.0c12088 ◽

2021 ◽

Author(s):

Cameron L. Brown ◽

Brandon H. Bowser ◽

Jan Meisner ◽

Tatiana B. Kouznetsova ◽

Stefan Seritan ◽

...

Keyword(s):

Ring Opening ◽

Substituent Effects ◽

Ring Opening Reactions

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ChemInform Abstract: Discovery of μ-Opioid Selective Ligands Derived from 1-Aminotetralin Scaffolds Made via Metal-Catalyzed Ring-Opening Reactions.

ChemInform ◽

10.1002/chin.200929090 ◽

2009 ◽

Vol 40 (29) ◽

Author(s):

Chris Dockendorff ◽

Shujuan Jin ◽

Madeline Olsen ◽

Mark Lautens ◽

Martin Coupal ◽

...

Keyword(s):

Ring Opening ◽

Ring Opening Reactions ◽

Selective Ligands ◽

Metal Catalyzed

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Stereoselective Synthesis of Tetraalkyl Cyclobutene-1,2,3,4-tetracarboxylates. Synthesis of Tetraalkyl (Z,Z)-Buta-1,3-diene-1,2,3,4-tetracarboxylates

Journal of Chemical Research ◽

10.1177/174751989902300829 ◽

1999 ◽

Vol 23 (8) ◽

pp. 512-513

Author(s):

Issa Yavari ◽

Farahnaz Nourmohammadian

Keyword(s):

Ring Opening ◽

Wittig Reaction ◽

Stereoselective Synthesis ◽

Intramolecular Wittig Reaction ◽

Ring Opening Reactions ◽

Boiling Toluene

Tetraalkyl cyclobutene-1,2,3,4-tetracarboxylates, prepared by intramolecular Wittig reaction between a vinylphosphonium salt and diethyl 2-oxobutanedioate, undergo electrocyclic ring-opening reactions, in boiling toluene, to produce highly electron-deficient 1,3-dienes.

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