Selective N-alkylation of amines with alcohols via hydrogen transfer catalyzed by copper complex in an ionic liquid media

A catalytic system containing a copper-Schiff base complex in ethyl methyl imidazolium hexafluoro phosphate [(EMIM)PF6] ionic liquid, where the ionic liquid was used as a solvent, was found to be very effective to catalyze the synthesis of benzazoles [i.e. imidazoles (C–N), thiazoles (C–S) and oxazo...

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Main Authors: N. Asharani, S. Shakeel Nawaz, S. Ranganatha, S. Supriya, Dileep Ramakrishna
Format: Article
Language:English
Published: Elsevier 2024-03-01
Series:Chemical Engineering Journal Advances
Subjects:
Online Access:http://www.sciencedirect.com/science/article/pii/S2666821124000036
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author N. Asharani
S. Shakeel Nawaz
S. Ranganatha
S. Supriya
Dileep Ramakrishna
author_facet N. Asharani
S. Shakeel Nawaz
S. Ranganatha
S. Supriya
Dileep Ramakrishna
author_sort N. Asharani
collection DOAJ
description A catalytic system containing a copper-Schiff base complex in ethyl methyl imidazolium hexafluoro phosphate [(EMIM)PF6] ionic liquid, where the ionic liquid was used as a solvent, was found to be very effective to catalyze the synthesis of benzazoles [i.e. imidazoles (C–N), thiazoles (C–S) and oxazoles (C–O)]. Substituted amines and alcohols reacted with each other in the given reaction conditions to give benzazoles. The reaction proceeded via a hydrogen transfer mechanism, which was proved by conducting series of reactions involving the conversion of aldehydes/ketones to corresponding primary and secondary alcohols. The reaction conditions were optimized with respect to catalyst concentration, best choice of the solvent, effect of different bases and the optimized chosen ones. It was found that the reaction required as low as 0.1 mol% of the catalyst and potassium carbonate as the base. Most interestingly the quantity of the products yielded the same when an equal ration of water: [EMIM]PF6 mixture was used as the solvent, same as when the ionic liquid alone was used as the solvent. A wide range of substituted alcohols and amines were tested and the products were formed within a short reaction time and comparatively good yields.
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spelling doaj.art-5fd1fb83ba8448fda8e9fcae6b02e1932024-02-03T06:39:46ZengElsevierChemical Engineering Journal Advances2666-82112024-03-0117100585Selective N-alkylation of amines with alcohols via hydrogen transfer catalyzed by copper complex in an ionic liquid mediaN. Asharani0S. Shakeel Nawaz1S. Ranganatha2S. Supriya3Dileep Ramakrishna4Department of Chemistry, Presidency University, Yelahanka, Bengaluru, 560064, IndiaDepartment of Chemistry, Acharya Institute of Graduate Studies, Bengaluru, 560107, IndiaDepartment of Chemistry, Presidency University, Yelahanka, Bengaluru, 560064, IndiaDepartment of Chemistry, BMS College of Engineering, Bull temple road, Bengaluru, 560019, India; Centre for Nanomaterials & Displays, BMS College of Engineering, Bull temple road, Bengaluru, 560019, IndiaDepartment of Chemistry, Presidency University, Yelahanka, Bengaluru, 560064, India; Corresponding author.A catalytic system containing a copper-Schiff base complex in ethyl methyl imidazolium hexafluoro phosphate [(EMIM)PF6] ionic liquid, where the ionic liquid was used as a solvent, was found to be very effective to catalyze the synthesis of benzazoles [i.e. imidazoles (C–N), thiazoles (C–S) and oxazoles (C–O)]. Substituted amines and alcohols reacted with each other in the given reaction conditions to give benzazoles. The reaction proceeded via a hydrogen transfer mechanism, which was proved by conducting series of reactions involving the conversion of aldehydes/ketones to corresponding primary and secondary alcohols. The reaction conditions were optimized with respect to catalyst concentration, best choice of the solvent, effect of different bases and the optimized chosen ones. It was found that the reaction required as low as 0.1 mol% of the catalyst and potassium carbonate as the base. Most interestingly the quantity of the products yielded the same when an equal ration of water: [EMIM]PF6 mixture was used as the solvent, same as when the ionic liquid alone was used as the solvent. A wide range of substituted alcohols and amines were tested and the products were formed within a short reaction time and comparatively good yields.http://www.sciencedirect.com/science/article/pii/S2666821124000036BenzazolesCopper complexesSchiff baseIonic liquidsImmobilization
spellingShingle N. Asharani
S. Shakeel Nawaz
S. Ranganatha
S. Supriya
Dileep Ramakrishna
Selective N-alkylation of amines with alcohols via hydrogen transfer catalyzed by copper complex in an ionic liquid media
Chemical Engineering Journal Advances
Benzazoles
Copper complexes
Schiff base
Ionic liquids
Immobilization
title Selective N-alkylation of amines with alcohols via hydrogen transfer catalyzed by copper complex in an ionic liquid media
title_full Selective N-alkylation of amines with alcohols via hydrogen transfer catalyzed by copper complex in an ionic liquid media
title_fullStr Selective N-alkylation of amines with alcohols via hydrogen transfer catalyzed by copper complex in an ionic liquid media
title_full_unstemmed Selective N-alkylation of amines with alcohols via hydrogen transfer catalyzed by copper complex in an ionic liquid media
title_short Selective N-alkylation of amines with alcohols via hydrogen transfer catalyzed by copper complex in an ionic liquid media
title_sort selective n alkylation of amines with alcohols via hydrogen transfer catalyzed by copper complex in an ionic liquid media
topic Benzazoles
Copper complexes
Schiff base
Ionic liquids
Immobilization
url http://www.sciencedirect.com/science/article/pii/S2666821124000036
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AT sranganatha selectivenalkylationofamineswithalcoholsviahydrogentransfercatalyzedbycoppercomplexinanionicliquidmedia
AT ssupriya selectivenalkylationofamineswithalcoholsviahydrogentransfercatalyzedbycoppercomplexinanionicliquidmedia
AT dileepramakrishna selectivenalkylationofamineswithalcoholsviahydrogentransfercatalyzedbycoppercomplexinanionicliquidmedia