Non-Isomorphic Chlorine - Bromine Substitution in the Copper(I) Halide π-Complexes with 1-Allyl-4-aminopyridinium

Abstract

By alternating-current electrochemical synthesis crystals of {Cu[H 2NC5H4N(C3H5)]Br 2}·H2O (I), {Cu[H2NC5H 4N-(C3H5)]Br0.65Cl 1.35}·H2O (II) and {Cu[H2NC 5H4N(C3H5)]Cl2} (III) π-complexes have been obtained and structurally investigated. The I and II compounds are isostructural and crystallize in a monoclinic sp. g.r. P2 1/c, I: a = 7.359(2) Å, b = 12.3880(6) Å, c = 13:637(3) Å, β = 107.03(1)°, V = 1188.7(4) Å3, Z = 4 for C8H13N2OBr2Cu composition, R = 0.0293 for 2140 reflections. II: a = 7.2771(6) Å, b = 12.3338(3) Å, c = 13.4366(7) Å, β = 107.632(2)°, V = 1149.3(1) Å 3, Z = 4 for C8H13N2Br 0.65Cl1.35Cu composition, R = 0.0463 for 2185 reflections. Metal and halogen atoms form centrosymmetric Cu2X4 dimers. Each copper atom is surrounded by three halogen atoms and by a weakly bonded C=C-group of the onium moiety. Isolated {Cu[H2NC 5H4N(C3H5)]}2X 4 dimers are combined into a three-dimensional network due to a bridging function of water molecules via a system of rather strong hydrogen bonds. Chlorine derivative in crystallizes in another structure type: sp. gr. C2/c, a = 21.568(7) Å, b = 7.260(2) Å, c = 13.331(3) Å, β = 95.65(2)°, V = 2077(2) Å3, Z = 8 for C 8H11N2Cl2Cu composition. Copper atom, included in CuCl2- isolated fragment, is coordinated to a C=C-bond of ligand moiety. N-H...Cl hydrogen bonds unite Cu[H2NC5H4N(C3H5)]Cl 2 subunits into infinite ribbons. π-Interaction in III appears to be more effective than in I and II.