Synthesis and Structure of New Trinuclear Zinc(II) Complexes with Hexanoic or 3-Vinylbenzoic Acid Anions and 1,10-Phenanthroline

Trinuclear complexes Zn3(vbzo)6(phen)2·4MeCN 1, Zn3(hex)6(phen)2 2 bearing anions of alkenyl- and alkyl-substituted 3-vinylbenzoic (vbzo) and hexanoic (hex) acids in combination with terminal 1,10-phenanthroline (phen) molecules are prepared for the first time and structurally characterized. In the linear trinuclear metal core, zinc(II) atoms are pairwise connected by two bridging and one chelate-bridging (1) or three bridging (2) carboxylate anions. In the crystal, supramolecular chains are formed due to π–π interactions between phenanthroline molecules (1, 2) as well as phenanthroline and vbzo molecules (1). In the crystal packing of 2, alkyl substituents of hex anions are oriented parallel to each other and form hydrophobic zones. The packings of 1 and 2 are additionally stabilized by a network of hydrogen bonds between O atoms of carboxylate anions and H atoms of phen molecules.