Silica Perchloric Acid Matrix Supported Ring Opening of Epoxide Under Microwave Radiation†

The regioselective epoxide ring opening at less substituted carbon atom of epoxide were reported by nucleophiles like heterocyclic amines which gives well known 1,2-difunctionalized amino alcohols. These are present in many synthetic as well as natural products. The ring opening of epoxide is achieved by cleavage with amines in presence of copper(0) as a catalyst. It is observed that the lithium napthalenide reduction of copper(I) produces a highly reactive form of copper(0) that acts as a catalyst for ring opening of epoxides with an amine.

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Functionalized dicyandiamide–formaldehyde polymers as efficient heterogeneous catalysts for conversion of CO2 into organic carbonates

Green Chemistry ◽

10.1039/c3gc42331j ◽

2014 ◽

Vol 16 (5) ◽

pp. 2771-2778 ◽

Cited By ~ 59

Author(s):

Xiang-Lei Meng ◽

Yi Nie ◽

Jian Sun ◽

Wei-Guo Cheng ◽

Jin-Quan Wang ◽

...

Keyword(s):

High Activity ◽

Ring Opening ◽

Heterogeneous Catalysts ◽

Transesterification Reaction ◽

Organic Carbonates ◽

Ring Opening Of Epoxide

The ABMDFP exhibited high activity on cycloaddition of CO2 and transesterification reaction of EC, which was also suitable for various substrates. A possible mechanism of ring-opening of epoxide and activation of CO2 was proposed.

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Synthesis of New Bimetallic Chiral Salen Catalyst Bearing Co(BF4)2Salt and Its Application in Asymmetric Ring Opening of Epoxide

Bulletin of the Korean Chemical Society ◽

10.5012/bkcs.2010.31.10.2973 ◽

2010 ◽

Vol 31 (10) ◽

pp. 2973-2979 ◽

Cited By ~ 11

Author(s):

Yong-Suk Kim ◽

Choong-Young Lee ◽

Geon-Joong Kim

Keyword(s):

Ring Opening ◽

Ring Opening Of Epoxide ◽

Asymmetric Ring Opening

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Phosphonium-Based Porous Ionic Polymer with Hydroxyl Groups: A Bifunctional and Robust Catalyst for Cycloaddition of CO2 into Cyclic Carbonates

Polymers ◽

10.3390/polym12030596 ◽

2020 ◽

Vol 12 (3) ◽

pp. 596

Author(s):

Yizhu Lei ◽

Yali Wan ◽

Wei Zhong ◽

Dingfu Liu ◽

Zhou Yang

Keyword(s):

Ring Opening ◽

Active Sites ◽

Active Catalyst ◽

Hydroxyl Groups ◽

Cyclic Carbonates ◽

Initial Activity ◽

Ionic Polymer ◽

Hierarchical Pore Structure ◽

Ring Opening Of Epoxide ◽

Hierarchical Pore

The integration of synergic hydrogen bond donors and nucleophilic anions that facilitates the ring-opening of epoxide is an effective way to develop an active catalyst for the cycloaddition of CO2 with epoxides. In this work, a new heterogeneous catalyst for the cycloaddition of epoxides and CO2 into cyclic carbonates based on dual hydroxyls-functionalized polymeric phosphonium bromide (PQPBr-2OH) was presented. Physicochemical characterizations suggested that PQPBr-2OH possessed large surface area, hierarchical pore structure, functional hydroxyl groups, and high density of active sites. Consequently, it behaved as an efficient, recyclable, and metal-free catalyst for the additive and solvent free cycloaddition of epoxides with CO2. Comparing the activity of PQPBr-2OH with that of the reference catalysts based on mono and non-hydroxyl functionalized polymeric phosphonium bromides suggested that hydroxyl functionalities in PQPBr-2OH showed a critical promotion effect on its catalytic activity for CO2 conversion. Moreover, PQPBr-2OH proved to be quite robust and recyclable. It could be reused at least ten times with only a slight decrease of its initial activity.

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Salalen vs. thiolen: in the ring(-opening of epoxide and cyclic carbonate formation)

New Journal of Chemistry ◽

10.1039/d0nj00725k ◽

2020 ◽

Vol 44 (15) ◽

pp. 6063-6067 ◽

Cited By ~ 2

Author(s):

Oliver J. Driscoll ◽

Jack A. Stewart ◽

Paul McKeown ◽

Matthew D. Jones

Keyword(s):

Ring Opening ◽

Cyclic Carbonate ◽

Cyclohexene Oxide ◽

Chloride Complexes ◽

Carbonate Formation ◽

Ring Opening Of Epoxide

A range of Fe(iii)-salalen and -thiolen–chloride complexes have been prepared and are shown to be active catalysts for the selective coupling of CO2 and cyclohexene oxide (CHO).

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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

<p>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-(<i>N</i>-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.</p>

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