Self-assembly of porous two-dimensional copper(II) α, β-unsaturated carboxylate complexes with trimethyl phosphate

Abstract

A new type of two-dimensional network was found in the hydrogen-bonded molecular assemblies of copper(II) α,β-unsaturated carboxylate complexes with TMP [OP(OMe)3], {Cu2A4(H2O)2[OP(OMe)3]}n [(1) A = CH2=CHCO2−; (2) A = CH2=C(Me)CO2−]. The crystal structure of (1) has been determined by single-crystal X-ray diffraction. Both complexes are unique in terms of a sheet structure brought about by O—H ⋯ O hydrogen-bonded interactions both between neighbouring Cu2A4(H2O)2 units and between Cu2A4(H2O)2 and OP(OMe)3 molecules. The electronic reflectance spectra in the solid state suggest a square pyramidal coordination environment around the copper(II) atom. Room temperature X-band e.s.r. spectra of powered samples and variable-temperature magnetic susceptibility studies indicate the presence of strong antiferromagnetic exchange interactions between two copper(II) atoms, with 2J = −310 cm−1 for (1) and 2J = −304 cm−1 for (2) respectively.