Malays. J. Anal. Sci. Volume 30 Number 3 (2026): 1820

 

Research Article

 

Cu₃(BTC)₂ metal organic framework as a recyclable heterogeneous catalyst for the synthesis of N substituted urea via aldehyde–urea condensation

 

Nwogu Uchemadu Ephraim1,2, Mohamed Ibrahim Mohamed Tahir1,3, Emilia Abdulmalek1,2, Norhayu Asib4, and Mohd Basyaruddin Abdul Rahman1,2,3

 

1Department of Chemistry, Faculty of Science, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor Darul Ehsan, Malaysia

2Integrated Chemical Biophysics Research, Faculty of Science, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor Darul Ehsan, Malaysia

3Foundry of Reticular Materials for Sustainability (FORMS), Faculty of Science, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor Darul Ehsan, Malaysia

4Department of Plant Protection, Faculty of Agriculture, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor Darul Ehsan, Malaysia

 

 *Corresponding author: basya@upm.edu.my

                                           

Received: 8 April 2026; Revised: 10 May 2026; Accepted: 18 May 2026; Published: 30 June 2026

Abstract

In this study, an environmentally friendly synthesis of N-substituted urea derivatives was achieved using copper benzene-1,3,5-tricarboxylate metal–organic framework (Cu₃(BTC)₂-MOF) as a heterogeneous catalyst, addressing limitations of conventional homogeneous acid-catalyzed methods, which are corrosive, poorly recyclable, and environmentally undesirable. The catalytic performance of Cu₃(BTC)₂-MOF was evaluated in absolute ethanol at 60 °C for 50 min using furfural and urea as model substrates. The structural integrity of the MOF catalyst was confirmed by PXRD analysis. Under the optimized conditions, Cu₃(BTC)₂-MOF afforded N-(furan-2-ylmethylene)-urea in a moderate yield of 62.1%. The product structure was confirmed by FTIR and ¹H NMR spectroscopy. The catalytic activity is attributed to accessible Lewis acidic Cu(II) sites, which activate the aldehyde carbonyl group and promote condensation with urea. The catalyst retained activity over three consecutive cycles with yields above 50%, indicating reasonable stability and recyclability. These findings demonstrate that Cu₃(BTC)₂-MOF is a reusable and environmentally benign catalyst for aldehyde–urea condensation reactions

 

Keywords: Cu3(BTC)2, metal–organic framework, N-substituted urea, furfural, urea

 

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