Functional Porphyrinic Metal–Organic Framework as a New Class of Heterogeneous Halogen‐Bond‐Donor Catalyst.

Biomimetic metal‐organic frameworks have attracted great attention as they can be used as bio‐inspired models, allowing us to gain important insights into how large biological molecules function as catalysts. In this work, we report the synthesis and utilization of such a metal‐metalloporphyrin framework (MMPF) that is constructed from a custom‐designed ligand as an efficient halogen bond donor catalyst for Diels–Alder reactions under ambient conditions. The implementation of fabricated halogen bonding capsule as binding pocket with high‐density C−Br bonds enabled the use of halogen bonding to facilitate organic transformations in their three‐dimensional cavities. Through combined experimental and computational studies, we showed that the substrate molecules diffuse through the pores of the MMPF, establishing a host‐guest system via the C−Br⋅⋅⋅π interaction. The formation of halogen bonds is a plausible explanation for the observed boosted catalytic efficiency in Diels–Alder reactions. Moreover, the unique capability of MMPF highlights new opportunities in using artificial non‐covalent binding pockets as highly tunable and selective catalytic materials. [ABSTRACT FROM AUTHOR]