Synthesis and coordination to the coinage metals of a trimethylpyrazolyl substituted 3-arylacetylacetone

Abstract

AbstractThe ligand 3-(4-(1,3,5-trimethyl-1H-pyrazol-4-yl)phenyl)acetylacetone (1) combines a Pearson hard O,O′ chelating acetylacetone donor with a softer pyrazole N donor bridged by a phenylene spacer. Deprotonation and coordination to CuIIleads to a square planar bis-acetylacetonato complex; interpreting the close proximity of an adjacent complex’s pyrazole moiety as anη2${{\eta}}^{2}$coordination to the axial CuIIposition leads to a two dimensional extended structure. The N donor capabilities are proven by coordination to AgPF6and AuCl; for AgIa cationic linear bis-pyrazole complex as a toluene solvate is obtained with toluene-pyrazole π-interactions and an essentially uncoordinatedPF6-${{\mathrm{PF}}_{6}}^{-}$anion. In the case of AuCl a neutral linear coordination compound with one chlorido and one pyrazole ligand1is obtained. Comparing the dihedral angles with a closely related but shorter ligand reveals a larger rotational degree of freedom in1, allowing for richer architectures in emerging coordination polymers.