Effects of strong hydrogen bonds and weak intermolecular interactions on supramolecular assemblies of 4-fluorobenzylamine

A series of supramolecular salts have been obtained by the self-assembly of 4-fluorobenzylamine and halide ions or metal chloride with 18-crown-6 as the host in the hydrochloric acid medium, i.e. (C7H9FN)(+)center dot X- (X = Cl-, 1; Br-, 2), [(C7H9FN)(2)center dot(18-crown-6)(2)](2+)center dot(MCl4)(2-) (M = Mn, 3; Co, 5; Zn, 7; Cd, 8), [(C7H9FN)center dot(18-crown-6)](+)center dot(FeCl4)(-) (4) and [(C7H9FN)center dot(18-crown-6)](+)center dot 1/2(CuCl4)(2-) (6). Structural analyses indicate that 1-2 crystallize in the triclinic space group P-1, 4 in orthorhombic space group Prima and 3, 5, 6-8 in the monoclinic space group P2(1)/c or C2/c. In these compounds, extensive intermolecular interactions have been utilized for the self-assembly of diverse supramolecular architectures, ranging from strong N-H center dot center dot center dot X (X = O, Cl, Br) hydrogen bonds to weak C-H center dot center dot center dot Y (Y= F, Cl, pi) interactions. N-H center dot center dot center dot Cl/Br hydrogen bonds offer the major driving force in the crystal packing of salts 1-2 while N-H center dot center dot center dot O hydrogen bonds are found in salts 3-8. (C) 2015 Elsevier B.V. All rights reserved.