A new Zr­(IV)-based UiO-67 metal–organic framework (1) was prepared with urea-functionalized biphenyl-4,4′-dicarboxylic acid (BPDC-urea) as the linker using conventional solvothermal technique and thoroughly characterized using X-ray powder diffraction (XRPD), Fourier transform infrared (FT-IR) spectroscopy, thermogravimetric (TG), and N2 sorption analyses. The activated form of 1 (called 1′) exhibited excellent BET surface area in spite of having a large functional moiety (urea) in the linker side. The activated form of this material (1′) was successfully employed for the Friedel–Crafts alkylation of indole with β-nitrostyrene to achieve 97% yield in toluene at 70 °C for 24 h. Furthermore, the catalyst was used for four cycles, with no significant loss in its activity, and the reaction was heterogeneous in nature. The activity of 1′ was comparable to UiO-67-(NH2)2, whereas the activity was 2-fold higher compared to the parent UiO-67. Further, the activity of the BPDC-urea linker was nearly 2-fold higher than that of ZrCl4, suggesting the crucial role played by the urea moiety than the metal node. In addition, the catalyst (1′) exhibited a wide substrate scope, allowing the preparation of a series of compounds with moderate to high yields under the optimized reaction conditions. The roles of metal salt and linker in the catalysis have also been studied separately, and the mechanism for the catalysis has been clarified.

A Zr(IV)‐based UiO‐66 metal‐organic framework (MOF) (named 1) was synthesized by employing 1‐(aminomethyl)naphthalene‐2‐ol appended terephthalate linker and Zr(IV) salt via solvothermal method and subsequently characterized. Furthermore, the potential efficiency of activated (named 1′) form of as‐synthesized MOF was investigated as an organocatalyst for the ring‐opening of epoxide by methanol. The catalytic performance of 1 and 1′ was studied in the methanolysis of styrene oxide as a model substrate and the activity of 1′ was also examined with various alcohols. Under the optimized reaction conditions, the catalytic performance of 1′ reached 96 % conversion of styrene oxide to its corresponding product with 98 % regioselectivity. The reusability and stability of the catalyst were proved by recycling up to four runs in the methanolysis of styrene oxide. The Lewis acidity originating from metal nodes and hydrogen bond donating (HBD) sites in the linker is distributed homogeneously throughout the framework, thus playing crucial role in the activation of epoxide with easy accessibility.

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