Two‐Dimensional {Co³⁺–Co²⁺} and {Fe³⁺–Co²⁺} Networks and Their Heterogeneous Catalytic Activities

Abstract

We report the synthesis and characterization of two-dimensional homodimetallic {Co 3+ -Co 2+ } and heterodimetallic {Fe 3+ -Co 2+ } coordination networks with Co 3+ -and Fe 3+based metalloligands. The crystal structures reveal 2D networks in which the metalloligands are connected through secondary Co 2+ ions. The kinetic lability of the secondary [a]4966 Co 2+ ions, their Lewis acidity, and the presence of dissociable coordinated water molecules have been utilized in Knoevenagel condensation and cyanation reactions of assorted aldehydes. These reusable networks catalyze these reactions heterogeneously and efficiently.

Ethylene Polymerization Using Site‐Selective Pyridine‐Amide Based Iron Complexes

“…A variety of pyridine‐amide based transition metal complexes have been reported in the literature, such as cobalt(III), cobalt (II), iron(II),, iron(III),, manganese(II), nickel(II),, copper(II), rhodium(II), and ruthenium(III) ,. These studies indicated that designing of organic ligands and properly choosing metal ions are keys to create target transition metal‐based coordination complexes.…”

Three-Dimensional Heterometallic Coordination Networks: Syntheses, Crystal Structures, Topologies, and Heterogeneous Catalysis

“…[90][91][92][93] In this context, heterogeneous catalysts incorporating Lewis acidic sites are advantageous for the ease in catalyst separation and product isolation. [32][33][34][35][36][37][38][39][40]49,51 The successful performance of the present HCNs in KCs advocated their potential role in CRs as well. As displayed in Table 5, all four HCNs were able to catalyze CRs of assorted aldehydes using trimethylsilylcyanide as the cyanide source.…”

“…[32][33][34][35][36][37][38][39][40] In this context, Lewis acidic metal-based coordination networks have displayed noteworthy results by several groups including us. 49,51,[75][76][77][78][79][80][81][82][83][84][85] The catalytic activities of HCNs 3 -6 was investigated by employing several aromatic and heterocyclic aldehydes using malononitrile as an active methylene compound. In order to optimize the reaction conditions; HCN 3 was used as a representative catalyst for the KCs of benzaldehyde with malononitrile.…”

“…[41][42][43][44][45][46][47][48][49][50][51][52][53][54] Depending on the number, position, and orientation of the appended functional groups being offered from a metalloligand; we have been able to showcase the synthesis of hydrogen bonded assemblies, 41,42 trimetallic complexes [43][44][45][46] as well as ordered 2D and 3D architectures. [47][48][49][50][51][52][53][54] These examples illustrate the importance metalloligands for the construction of HCNs compared to homometallic networks typically obtained from the conventional reaction between a ligand and a metal ion. In addition, judicious selection of the Lewis acidic and/or redox-sensitive secondary metals in such designed materials has been utilized by displaying homogeneous as well as heterogeneous catalysis.…”

“…In addition, judicious selection of the Lewis acidic and/or redox-sensitive secondary metals in such designed materials has been utilized by displaying homogeneous as well as heterogeneous catalysis. [43][44][45][46][47][48][49][50][51][52][53][54] Herein, we report the syntheses, crystal structures, topological analyses, and catalytic properties of two {Co 3+ -Zn 2+ } and two {Co 3+ -Cd 2+ } HCNs using two different Co 3+ -based metalloligands offering appended aryl carboxylic acid groups. These HCNs display interesting network topologies including one unprecedented topology.…”