The relevance of the fluorine interactions in the supramolecular structure of a complex constructed from copper(II) hexafluoroacetylacetonate and the 40-(3-pyridyl)-2,20:60,200-terpyridine ligand. Novel C–F/p synthons involving the p-system of the terpyridine moieties and those of the hexafluoroacetylacetonate chelate rings

Abstract

Reaction of 40-(3-pyridyl)-2,20:60,200-terpyridine (pyterpy) with Cu(hfacac)2 (hfacac = hexafluoroacetylacetonate) led to the formation of the novel compound [Cu3(hfacac)4(m-pyterpy)2][Cu(hfacac)3]2 (1). The structure is composed of a trinuclear [Cu3(hfacac)4(m-pyterpy)2]2+ cation and two [Cu(hfacac)3] anionic species. The cation consists of a chain of three CuII atoms connected by bridging pyterpy ligands. The [Cu(hfacac)3] anions have the hfacac ligands coordinated in their usual chelating manner through their carbonyl O donors. Besides the coulombian forces, the ionic species are fixed by C–H O, C–H F, F F and a variety of unusual inter-ion C–F p interactions that control the packing motif. These p-interactions involve the terpyridine groups from the pyterpy ligand and the five-membered rings of the chelating hexafluoroacetylacetonate anions.