Crystal structure of aquabis(acrylato-O,O')(1,10-phenanthroline-N,N′)- cadmium(II), Cd(H2O)(C3H3O2)2(C12H10N2)

Abstract

C18H15CdN2O5, monoclinic, P121/n1 (no. 14), a = 9.9973(5) Å, b = 9.0433(4) Å, c = 19.4849(8) Å, b = 101.235(2)°, V = 1727.9 Å 3 , Z = 4, Rgt(F) = 0.025, wRref(F 2 ) = 0.065, T = 273 K. Source of materialThe title complex was prepared analogously to the synthesis of [CdCl(C3H3O2)(C12H10N2)2] except for the pH of this solution controlled in the range of 8-9 [1]. Freshly prepared precipitate Cd(OH)2, which was obtained from 1.0 ml (1.0 M) NaOH to a stirred aqueous solution of CdCl 2 · 6H2O (0.269 g, 1.0 mmol) in 5 ml H2O, was added to a stirred aqueous solution of 1,10-phenanthroline monohydrate (0.198 g, 1.0 mmol) and acrylic acid (0.144 g, 2.0 mmol) in 20 ml H2O/ethanol (1:1, v/v) . The mixture was further stirred for ca. 30 min at room temperature, and the pH of the mixture solution was controlled in the range of 8-9 with 1 M NaOH solution. The mixture then was further stirred for another 2 h and filtered off and the resultant filtrate was allowed to stand by slow evaporation at room temperature. The colorless blocklike crystals were obtained 30 days later (yield 80 % based on the Cd(OH)2 input). DiscussionThe title structure consists of Cd(H 2 O)(C 3 H 3 O 2 ) 2 (C 12 H 10 N 2 ) complex molecules, where the seven-coordinated Cd atom adopts a distorted monocapped octahedral environment formed by two nitrogen atoms of an 1,10-phenanthroline ligand and five oxygen atoms from one aqua ligand and two acrylato anion groups with the acrylato O2 atom residing at the cap site and the axial apical positions occupied by one aromatic pyridyl atoms (N2) and one acrylato O atom (O1) (figure, top). The equatorial plane sites are defined by one aromatic pyridyl N atom (N1), one aqua ligand (O5) and two acrylato O atoms (O3, O4) with the pyridyl N1 atom shifted from the basal plane of 0.9999(3) Å. The CdN2 length (2.3706(2) Å) is slightly longer than the CdN1 length (2.3676 (2) direction, the complex molecules are interlinked via the intermolecular hydrogen-bonding interactions into 1D double chains. The resulting chains are further held by p-p interactions between the 1,10-phenanthroline ligands of neighboring double chains into layers parallel to (101) with an average interplanar distance of 3.4522(5) Å (figure, bottom).