A Carboxylate-Rich Metalloligand and Its Heterometallic Coordination Polymers: Syntheses, Structures, Topologies, and Heterogeneous Catalysis

Abstract

This work reports three heterometallic coordination polymers (HCPs), namely, [{(1′) 2 Zn 8 Na 24), originated from a common Co 3+ based metalloligand 1 offering eight arylcarboxylic acid groups where 1′ and 1″ respectively contribute eight and six anionic carboxylate groups. The crystal structure analyses display three-dimensional nature of all three HCPs wherein metalloligands are connected through secondary metals. Detailed topological analyses illustrate that the metalloligands function as the nodes that are connected to secondary building units (SBUs) composed of Zn 2+ , Cd 2+ , and Mn 2+ ions coordinated by the arylcarboxylate groups. All three HCPs effectively function as the heterogeneous catalysts for the Lewis acid assisted Knoevenagel condensation reactions of assorted aldehydes with three different active methylene compounds.

Coordination-polymer anchored single-site ‘Pd-NHC’ catalyst for Suzuki-Miyaura coupling in water

“…Coordination polymers (CPs) have been used as heterogeneous support because of its easily tunable electronic and structural properties. [10][11][12][13][14] CPs are constituted by linking metal centres with well-defined organic ligands. These materials have been widely used in sorption, separation, sensing, ion-exchange and transport, proton conduction, optics, magnetic materials, and catalysis.…”

Coordination driven architectures based on metalloligands offering appended carboxylic acid groups

“…1 This approach relies on developing a metalloligand that is capable of placing the appended functional groups to limited directions and therefore such functional groups can bind to the secondary metal ions in limited geometrical manner. [35][36][37] As a result of structural rigidity being offered by a metalloligand, the resultant CPs are often structurally predictable -a landmark step towards predictable architectures. 1,[35][36][37] There are several other advantages with the metalloligand approach: (i) this strategy allows selecting a primary metal ion (within a metalloligand) in addition to a secondary metal ion and as a result offers easy access to heterometallic CPs; (ii) facile selection of both primary and secondary metals allows placing desirable metals in close proximity; (iii) facile selection of secondary metals allows choices over desirable d-block as well as f -block elements.…”

“…However, the most common functional groups that are being offered by a metalloligand are heterocyclic rings (mostly pyridine) 1 and carboxylic acids. [35][36][37][38] A significant amount of work has been done as well as reviewed for the metalloligands offering appended heterocyclic rings, 1 particularly pyridine and therefore this article will not cover such metalloligands and their CPs. This perspective summarizes a variety of metalloligands offering appended carboxylic acid groups with a focus on the design strategies to understand the architectures of the resultant CPs.…”

Syntheses, Structures and Properties of 3d-4f Heterometallic Coordination Polymers Based on Tetradentate Metalloligand and Lanthanoid Ions

“…Current interest in these materials mainly focuses on the coordination polymers (CPs) associated with mixed-metal ions [5]. Among various approaches to the construction of heterometallic CPs, the most efficient one is to employ metalloligands that can connect with other metal centers, such as transition metal [6] [7] [8] and lanthanide ions [9]- [16]. For [26], alkaline-earth ions [27].…”