Spontaneous Synthesis of [Fe (Atrz) ]SO and its Analogues Through Accelerated Ageing: New Insights from Small-Scale Reactions.

Accelerated ageing reactions that take place between two solid materials on contact in the absence of added solvent have been used to synthesize two spin-crossover-active 1D coordination polymers and one of their Cu(II) analogues. The hygroscopy of the ligands and the relative humidity of the reaction chamber have been shown to be particularly important factors in the rate of reaction. Small-scale reactions between a few individual crystals have allowed observation of deliquescence of the 4-aminotriazole ligand at high humidity.

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

The role of ligand basicity in complex formation has been investigated using monodentate pyridyls or benzimidazole (mP) in combination with a solution-stable species derived form a coordination polymer, [Cu(L)] (where L = 2-(2-hydroxybenzylidene-amino)phenol). The 12 [Cu(L)(mP)n] complexes generated, combined with the {[Cu(L)]2(pP)} complexes from our previous work (where pP is a polypyridyl ligand), allow us to gauge the likelihood of complex formation based on the pKa of the conjugate acid of the pyridyl ligands and Hammett parameter, σ. Above pKa ≈ 4.

Hydrogen-bonding chain and dimer motifs in pyridinium and morpholinium hydrogen oxalate salts.

We present here three compounds consisting of pyridinium or morpholinium hydrogen oxalates, each displaying different hydrogen-bonding motifs, resulting in chains for 4-(di-methyl-amino)-pyridinium hydrogen oxalate 0.22-hydrate, CHN ·CHO ·0.22HO (), dimers for 4--butyl-pyridinium hydrogen oxalate, CHN·CHO (), and chains for morpholin-ium hydrogen oxalate, CHNO·CHO ().