Coordination polymers and metal–organic frameworks based on paddlewheel-type dirhodium(II) tetracarboxylates

Self‐Supported Heterogeneous Dirhodium(II) Catalyst for Nitrene and Carbene Transfer Reactions

“…To our knowledge, no coordinatively 3-dimensional extended materials exist built on axially-uncoordinated Rh 2 A 4 paddlewheels. 23 In contrast, molecular self-assemblies containing axially-free Rh 2 A 4 groups have been prepared in the form of molecular squares 24 and larger metal-organic polyhedra (MOP). 25 Inspired by the lack of Rh 2 A 4 materials combining 3dimensionality into a porous framework while preserving the catalytically-relevant axial coordination sites, we desired to find a ligand that could be used to produce a solid-state coordination polymer with 3-dimensionality that would have high catalytic activity for nitrene and carbene transfer reactions.…”

Ferrocene-Bearing Homoleptic and Heteroleptic Paddlewheel-Type Dirhodium Complexes

“…Fca-bearing paddlewheel-type Rh2 complexes are considered to be particularly interesting because this type of Rh2 complex shows excellent functional properties such as catalysis, sensing, and antitumor activities [29][30][31][32][33][34][35][36][37]. Homoleptic paddlewheel-type Rh2 complexes bridged with four fca derivative ligands, for example, [Rh2(fca)4], act as catalysts for carbene insertion, shape-selective alkane functionalization, and asymmetric intramolecular C-H insertion reactions [26,27,38]; however, the details of the synthesis, characterization, electrochemical and absorption properties, and X-ray crystal structures of the Rh2 complexes have not been previously reported.…”

Fabrication of Polyoxometalate-Based Metal–Organic Frameworks Integrating Paddlewheel Rh2(OAc)4 for Visible-Light-Driven Oxidative Coupling of Amines

“…Polyoxometalates (POMs) are a class of discrete anionic metal–oxo clusters consisting of the early transition metals [Mo­(VI), W­(VI), V­(V), Nb­(V), and Ta­(V)] in the highest oxidation state. They have attracted much interest in the photocatalytic field because of their structural diversity, high negative charge, and remarkable redox ability. , Particularly, POMs are often used as “electron relays” in photocatalytic organic synthesis reactions because they can achieve structural modifications at the molecular level and enable fast, reversible, and multiple electron transfer. − However, POMs usually absorb only UV light and have high solubility in the reaction system, making them difficult to recycle and reuse, greatly restricting their usage. − To address this challenge, various supports, including zeolites, cationic carbon nanotubes, covalent organic frameworks, and metal–organic frameworks (MOFs), have been employed for the construction of heterogeneous POM-based photocatalysts. − Among these different supports, the porous structure and rich chemical tunability of MOFs make them very promising candidates for the fabrication of POM-based MOFs (POMOFs), which are reusable and possess enhanced photocatalytic properties. , The immobilization of POMs onto MOFs by the judicious selection of ligands or metal nodes not only enables one to tune the lowest unoccupied molecular orbital (LUMO) energy levels of POMs but also to preserve and enhance the functionality of individual components. , Especially, Rh 2 paddlewheel complexes are considered to be some of the most promising building blocks for the construction of MOFs because of their high symmetry and interesting functions in areas of photocatalytic reactions, solar energy conversion, and molecular sensing. − It is speculated that the combination of Rh 2 paddlewheel complexes and POMs to constitute novel POMOFs could not only overcome the deficiencies of POMs but also make full use of their synergistic effects, thus boosting the photocatalytic activity.…”