Molecular structure of the 2:2 complex of cyclic oxaalkyl diamide of o-phthalic acid with sodium perchlorate

Structure of the 2:2 complex of cyclic oxaalkyl diamide of o-phthalic acid (CPhDA) with sodium perchlorate is studied by X-ray diffraction, ESI-MS, FT-IR, 1H and 13C NMR as well as PM5 semiempirical methods. The crystal space group is P21/n with a = 8.599(1) Å, b = 14.802(2) Å, c = 13.988(2) Å, β = 93.37(1)° and Z = 4. In the dimeric crystal structure each sodium cation is coordinated by oxygen atoms of two CPhDA molecules. The ESI-MS measurements have proved that in the gas phase the 2:2 (or 1:1) as well as 2:1 complexes are formed. In the acetonitrile solution the equilibrium between the 2:2 and 1:1 complexes is found. The structures of the 2:2, 1:1 and 2:1 complexes of CPhDA with sodium cation are visualized using the PM5 method and discussed in detail.