3-Nitrophenol–4,4′-bipyridylN,N′-dioxide (2/1): a DFT study and CSD analysis of DPNO molecular complexes

Abstract

The title 2:1 complex of 3-nitrophenol (MNP) and 4,4'-bipyridyl N,N'-dioxide (DPNO), 2C(6)H(5)NO(3) x C(10)H(8)N(2)O(2) or 2MNP.DPNO, crystallizes as a centrosymmetric three-component adduct with a dihedral angle of 59.40 (8) degrees between the planes of the benzene rings of MNP and DPNO (the DPNO moiety lies across a crystallographic inversion centre located at the mid-point of the C-C bond linking its aromatic rings). The complex owes its formation to O-H...O hydrogen bonds [O...O = 2.605 (3) A]. Molecules are linked by intermolecular C-H...O and C-H...N interactions forming R(2)(1)(6) and R(2)(2)(10) rings, and R(6)(6)(34) and R(4)(4)(26) macro-rings, all of which are aligned along the [1 01] direction, and R(2)(2)(10) and R(2)(1)(7) rings aligned along the [010] direction. The combination of chains of rings along the [1 01] and [010] directions generates the three-dimensional structure. A total of 27 systems containing the DNPO molecule and forming molecular complexes of an organic nature were analysed and compared with the structural characteristics of the dioxide reported here. The N-O distance [1.325 (2) A] depends not only on the interactions involving the O atom at the N-O group, but also on the structural ordering and additional three-dimensional interactions in the crystal structure. A density functional theory (DFT) optimized structure at the B3LYP/6-311G(d,p) level is compared with the molecular structure in the solid state.