The crystal structures of the acid salts of some monobasic acids. Part XIII. Potassium hydrogen dianisate (di-p-methoxybenzoate)

Abstract

The hydrogen dianisates of potassium and of rubidium MH(O₂C·C₆H₄·OMe)₂(M = K or Rb) are isomorphous. The crystal structure of the potassium salt, which has four molecules in the unit cell with a= 35·77, b= 7·05, and c= 6·16 Å, belonging to the space group Pbcn, has been determined, and refined to R= 15% for 1 200 independent reflexions. The structure is that of a Type A acid salt, the two anisate residues being connected by a hydrogen bond, across a two-fold axis, with O⋯H⋯O distance 2·476 ± 18 Å. The structure is compared with that of free anisic acid.