A Bridge Too Far: Testing the Limits of Polypyridyl Ligands in Bridging Soluble Subunits of a Coordination Polymer

Abstract

Starting with a coordination polymer, {[Cu(L)]2}n (1 where H2L = salicylidene-2-aminophenol), we have explored the ability of polypyridyl ligands (P) to bridge the monomer complex to form nine {[Cu(L)]2(P)} complexes. The identity and solution stability of the [Cu(L)] units has been investigated through a novel combined UV-vis/EPR experiment and it has been found to be a stable supramolecular building unit for the construction of discrete complexes and coordination polymers. The reorganisation of [Cu(L)] units to a new coordination polymer on addition of 4,4'-bipyridine markedly changes the connectivity of the structure and the magnitude of the antiferromagnetic interactions through reorientation of the Cu(II) orbitals. We also present the structure of 1, 80 years after its synthesis was first reported.

Trinodal Self-Penetrating Nets from Reactions of 1,4-Bis(alkoxy)-2,5-bis(3,2’:6’,3’’-terpyridin-4’-yl)benzene Ligands with Cobalt(II) Thiocyanate

“…Despite the fact that Cave and Raston reported the synthesis of bis(4,2':6',4''-terpyridin-4'-yl)benzene in 2001 [19], the coordination chemistry of bis(4,2':6',4''-tpy) ligands has only developed significantly in the last few years. With phenylene spacers, the ligands are only poorly soluble [16,20], but the introduction of solubilizing alkoxy substituents increases solubility in CHCl3 and allows the development of a versatile toolbox of functionalities for tuning their electronic and steric properties. We have recently reviewed our own progress in the coordination chemistry of ditopic and tetratopic ligands with 4,2':6',4''-tpy metal-binding domains [21].…”

All about that base: investigating the role of ligand basicity in pyridyl complexes derived from a copper-Schiff base coordination polymer

“…4,5 The size of this family gives coordination chemists a large variety of ligands to explore when constructing pyridyl complexes for catalysis, [6][7][8] spin crossover, 9,10 molecular magnets, 11,12 coordination polymers, [13][14][15] metal-organic frameworks, 16,17 medical imaging and therapeutic agents. 18,19 In our previous work, 20 we investigated the role of solubility of polypyridyl ligands (P) in the construction of coordination polymers and complexes synthesised from a copper Schiff-base starting material, {[Cu(L)]2}n, (compound 1, where L = 2-[(2hydroxybenzylidene)amino]phenol. Compound 1 is a onedimensional coordination polymer that can dissolve in DMSO to give [Cu(L)(DMSO)n] 'coordination monomer' complexes in solution.…”

Conformation-Selective Self-Assembly of Pd6 Trifacial Molecular Barrels Using a Tetrapyridyl Ligand

“…Ligand L was synthesized following the reported method by treating terephthaldehyde with sodium hydroxide, followed by the reaction with 3-acetylpyridine and ammonium hydroxide in ethanol . The reaction of L with M1 in a 1:2 molar ratio in water at 60 °C overnight resulted in a colorless solution.…”

“…23−27 Ligand L was synthesized following the reported method by treating terephthaldehyde with sodium hydroxide, followed by the reaction with 3-acetylpyridine and ammonium hydroxide in ethanol. 28 The reaction of L with M1 in a 1:2 molar ratio in water at 60 °C overnight resulted in a colorless solution. 1 H NMR of the resulting solution in D 2 O displayed a complex spectrum containing several broad and unassignable aromatic peaks (Figure S1) due to the formation of multiple assemblies.…”