Mixed cobalt/nickel metal–organic framework, an efficient catalyst for one-pot synthesis of substituted imidazoles

• Published in: Monatshefte für Chemie 2017-02, Vol.148 (2), p.347-355
• Main Authors: Ramezanalizadeh, Hamed, Manteghi, Faranak
• Format: Article
• Language: English
• Subjects: Aldehydes; Ammonium acetate; Analytical Chemistry; Benzil; Benzoin; Bimetals; Catalysts; Catalytic activity; Chemical synthesis; Chemistry; Chemistry and Materials Science; Chemistry/Food Science; Cobalt; Field emission microscopy; Field emission spectroscopy; Fourier transforms; Imidazole; Infrared analysis; Infrared spectroscopy; Inorganic Chemistry; Metal-organic frameworks; Nickel; Organic Chemistry; Original Paper; Physical Chemistry; Substitutes; Terephthalic acid; Theoretical and Computational Chemistry; Thermogravimetric analysis
• ISSN: 0026-9247; 1434-4475
• DOI: 10.1007/s00706-016-1776-9

In the present work, a three-dimensional bimetallic metal–organic framework, [CoNi(µ 3 -tp) 2 (µ 2 -pyz) 2 ] (tp = terephthalic acid, pyz = pyrazine) was applied as a highly efficient and recoverable heterogeneous catalyst. The catalyzed reaction was the one-pot three-component condensation reaction between benzil or benzoin with various substituted aromatic aldehydes and ammonium acetate to synthesize the corresponding imidazoles in solvent-free conditions and high to quantitative yields. The catalyst can be recycled at least five times without significant loss in the catalytic activity. To the best of our knowledge, 2,4,5-trisubstituted 1 H -imidazoles were not previously synthesized using MOFs as heterogeneous catalyst. The structure of previously reported cobalt/nickel MOF has been confirmed by various techniques, such as X-ray diffraction, thermogravimetric analysis, Fourier transform infrared spectroscopy, field emission scanning electron microscopy, energy dispersive X-ray spectroscopy, and Brunauer–Emmett–Teller. Graphical abstract