Molecular Engineering of Metal–Organic Layers for Sustainable Tandem and Synergistic Photocatalysis

Abstract

Metal–organic layers (MOLs), a monolayered version of metal–organic frameworks (MOFs), have recently emerged as a novel two-dimensional molecular material platform to design multifunctional catalysts. MOLs inherit the intrinsic molecular tunability of MOFs and yet have more accessible and modifiable building blocks. Here we report molecular engineering of six MOLs via modulated solvothermal synthesis between HfCl4 and three photosensitizing ligands followed by postsynthetic modification with two carboxylate-containing cobaloximes for tandem and synergistic photocatalysis. Morphological and structural characterization by transmission electron microscopy and atomic force microscopy and compositional analysis by inductively coupled plasma-mass spectrometry and nuclear magnetic resonance spectroscopy establish the MOLs as flat nanoplates with a periodic lattice structure of hexagonal symmetry. The MOLs efficiently catalyze tandem dehydrogenative coupling reactions and synergistic Heck-type coupling reactions. The most active MOL catalyst was used for the gram-scale synthesis of vesnarinone, a cardiotonic agent, in 80% yield with a turnover number of 400 and in eight consecutive reaction cycles without significant loss of activities.

Reticular framework materials for photocatalytic organic reactions

“…21f). 232 Compared to its homogenous counterparts, Hf-Ir-Co-PPA (PPA = 4-pyridinepropionic acid) exhibited the highest activity towards the tandem dehydrogenative coupling reactions between amines and cyclohexanones as well as the synergistic Heck-type coupling reactions between alkyl iodides and aryl olefins. Remarkably, Hf-Ir-Co-PPA could be used to synthesize vesnarinone, a cardiotonic drug, on the gram-scale with high yields and stability, emphasizing its tremendous potential in pharmaceuticals.…”

2D semiconductor nanosheets for solar photocatalysis

“…It is worth emphasizing that the combination of these methods, along with the advancement of new technologies, has given rise to several new approaches aimed at optimizing reaction conditions. These include surfactant‐assisted synthesis, 98 molecular modulation synthesis, 99 interfacial reaction synthesis, 97 and ultrasonic/microwave synthesis. The successful utilization of these techniques for preparing a 2D MOF has been demonstrated.…”

High-Capacity Iodine Adsorption and Nonporous to Porous Structural Transformation in an Originally Nonporous Coordination Polymer

“…Coordination polymers (CPs) have attracted much interest due to their diverse applications, including adsorption, [1][2][3] separation, [4][5][6] catalysis, [7][8][9] and sensing. [10][11][12] Adsorption is one of the key functions of this material, and almost all kinds of adsorbates, such as gases, organic vapours, and ions, can be captured by CPs.…”