4,4'-Bipyridine-cyano-acetic acid (1/2).

ABSTRACT

Crystals of the title adduct, C(10)H(8)N(2)·2C(3)H(3)NO(2), were obtained from a methanol/water solution of cyano-acetic acid and 4,4'-bipyridine at room temperature. In the crystal structure, cyano-acetic acid and centrosymmetric 4,4'-bipyridine mol-ecules are linked by O-H⋯N hydrogen bonds to form three-component supra-molecular adducts. The acidic H atom is almost midway between the O and N atoms of the cyano-acetic acid and bipyridine mol-ecules, with O-H and N-H distances of 1.19 (3) and 1.39 (3) Å, respectively, so that the H-atom transfer is best regarded as partial. The three-component adducts are further inter-connected with neighboring mol-ecules by weak inter-molecular C-H⋯O and C-H⋯N hydrogen bonds and by π-π stacking inter-actions [centroid-centroid distance = 3.7200 (11) Å] to generate a three-dimensional supra-molecular structure.