Zeolitic Imidazolate Frameworks ZIF-8 and MAF-5 as Highly Efficient Heterogeneous Catalysts for Synthesis of 1-Methoxy-2-propanol from Methanol and Propylene Oxide

Herein, we demonstrated that zinc zeolitic imidazolate frameworks (ZIFs) based on 2-methylimidazole (ZIF-8) and 2-ethylimidazole (MAF-5 or ZIF-14) linkers could be used as effective heterogeneous catalysts for catalytic synthesis of 1-methoxy-2-propanol (1-MP) that is widely used in industry due to its negligible toxicity as an ecofriendly solvent and as an intermediate for the synthesis of different chemicals. Application of these materials decreased the reaction temperature to 110 degrees C. 1-MP was found to be the major product, with 92.1-93.8% selectivity. The activity of MAF-5 was higher than that of ZIF-8. This difference can be explained by the high basicity of MAF-5. MAF-5 and ZIF-8 materials showed good reusability for 5 cycles in catalysis, which indicates their high potential for catalytic applications. Compared with reported catalysts, the studied ZIFs, especially MAF-5, showed not only the highest conversion of PO but also the highest selectivity for 1-MP under similar reaction conditions