This work reports the synthesis of pyridyltriazol-functionalized UiO-66 (UiO stands for University of Oslo), namely UiO-66-Pyta, from UiO-66-NH 2 through three post-synthetic modification (PSM) steps. The good performance of the material derives from the observation that partial formylation (~21% of -NHCHO groups) of H 2 BDC-NH 2 by DMF, as persistent impurity, takes place during synthesis of the UiO-66-NH 2 . Thus, to enhance material performance, firstly, the as-synthesized UiO-66-NH 2 was deformylated to give pure UiO-66-NH 2 . Subsequently, the pure UiO-66-NH 2 was converted to UiO-66-N 3 with nearly complete conversion (~95 %). Finally, the azide-alkyne[3+2]-cycloaddition reaction of 2-ethynylpyridine with the UiO-66-N 3 gave the UiO-66-Pyta. The porous MOF was then applied for the solidphase extraction of palladium ions from aqueous medium. Affecting parameters on extraction efficiency of Pd(II) ions were also investigated and optimized. Interestingly, UiO-66-Pyta exhibited selective and superior adsorption capacity for Pd(II) with maximum sorption capacity of 294.1 mg g -1 at acidic pH (4.5). The limit of detection (LOD) was found to be 1.9 µg L -1 . The estimated intra-day and inter-day precisions are 3.6% and 1.7%, respectively. Moreover, the adsorbent was regenerated and reused for 5 cycles without any significant change in the capacity and repeatability. The adsorption mechanism was described based on various techniques such as FT-IR, PXRD, SEM/EDS, ICP-AES, and XPS analyses as well as density functional theory (DFT) calculations. Notably, as a case study, the obtained UiO-66-Pyta after palladium adsorption, UiO-66-Pyta-Pd, was used as an efficient catalyst for Suzuki-Miyaura cross-coupling reaction.

The review summarizes the state-of-the-art of C–H active transformations over crystalline and amorphous porous materials as new emerging heterogeneous (photo)catalysts.

A porous multifunctional zirconium‐based metal–organic framework (MOF) was achieved by combined covalent and dative post synthetic modification (PSM) of the UiO‐66‐NH2, and characterized by a variety of techniques, including FTIR spectroscopy, powder XRD, N2 temperature‐programmed adsorption/desorption, scanning electron microscopy, thermal gravimetric analysis, inductively coupled plasma atomic emission spectroscopy, and UV/Vis diffuse reflectance spectroscopy. The MOF (Zr–MOF–FePC, PC=2‐pyridinecarboxaldehyde) is an active, efficient, and reusable catalyst for the one‐pot tandem photooxidative Passerini three‐component reaction of alcohols. This is a new type of tandem photocatalyst and cooperative catalyst and was obtained in the course of developing MOFs as versatile heterogeneous catalysts for diverse tandem oxidative multicomponent reactions. This work illustrates the potential of MOFs as multifunctional heterogeneous catalysts for sustainable chemistry.

Organic photochemistry is intensely developed in the 1980s, in which the nature of excited electronic states and the energy and electron transfer processes are thoroughly studied and finally well‐understood. This knowledge from molecular organic photochemistry can be transferred to the design of covalent organic frameworks (COFs) as active visible‐light photocatalysts. COFs constitute a new class of crystalline porous materials with substantial application potentials. Featured with outstanding structural tunability, large porosity, high surface area, excellent stability, and unique photoelectronic properties, COFs are studied as potential candidates in various research areas (e.g., photocatalysis). This review aims to provide the state‐of‐the‐art insights into the design of COF photocatalysts (pristine, functionalized, and hybrid COFs) for organic transformations. The catalytic reaction mechanism of COF‐based photocatalysts and the influence of dimensionality and crystallinity on heterogenous photocatalysis performance are also discussed, followed by perspectives and prospects on the main challenges and opportunities in future research of COFs and COF‐based photocatalysts.

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A new porphyrin-based porous organic polymer (POP) with BET surface area ranging from 780 to 880 m2/g was synthesized in free-base form via the reaction of meso-tetrakis(pentafluorophenyl) porphyrin and a rigid trigonal building block, hexahydroxytriphenylene. The material was then metallated with Fe(III) imparting activity for Lewis acid catalysis (regioselective methanolysis ring-opening of styrene oxide), oxidative cyclization catalysis (conversion of bis(2-hydroxy-1-naphthyl)methanes to the corresponding spirodienone), and a tandem catalytic processes: an in situ oxidation-cyclic aminal formation-oxidation sequence, which selectively converts benzyl alcohol to 2-phenyl-quinazolin-4(3H)-one. Notably, the catalyst is readily recoverable and reusable, with little loss in catalytic activity.

Introduction of metal−organic frameworks (MOFs) beyond metalcarboxylate series and their applications are still challenging. An innovative porous porphyrin catecholate iron-based MOF (PorphCat-Fe) with a Brunauer−Emmett− Teller (BET) surface area of 700 m 2 g −1 has been designed and synthesized through solvothermal self-assembling porphyrin catecholate linkers and iron(II) chloride as a cheap and earth-abundant node precursor. The structure was then evaluated with various techniques and utilized as an efficient and stable heterogeneous material for domino one-pot selective benzyl alcohol oxidation/Knoevenagel condensation reaction under visible LED light irradiation. The photocatalytic performance was remarkably improved as compared to individual components, affording excellent product yields (91%) with almost quantitative transformation of benzyl alcohol. The combination of Fe(III)-Lewis acidic sites and free-base porphyrin photosensitizers within the porous solid material make PorphCat-Fe able to show superior catalytic activity for this transformation. In addition, the MOF can easily accommodate the starting materials inside its mesopores and, thereby, make them easily accessible to active sites. This is an unusual example of an all-in-one noble metal-free bio-inspired supramolecular chemistry for an advanced organic transformation without the need of any chemical additive or further structural modification using only visible LED light conservation.

Fe(BTC) catalyzed synthesis of spirodienones and quinazolin-4(3H)-ones.