CRYSTAL-STRUCTURE OF THE 1-1-6 COMPLEX BETWEEN 18-CROWN-6, HYDROQUINONE AND WATER

Hydroquinone forms a 1 : 1 : 6 complex with 18-crown-6 and water. Crystals of this complex are monoclinic, space group P21/a with a = 14.289(1), b = 7.972(1), c = 11.596(1) Å, β = 97.72(1)°, Z = 2, Dc = 1.22 g cm-3. The hydroquinone and crown ether molecules lie on centres of symmetry with the crown in the D3 d conformation. The water molecules act as a bridge between hydroquinone and the crown ether. The structure consists of molecules linked by a 3-dimensional network of hydrogen bonds: the hydroquinone and two water molecules lie roughly in the (001) plane; the crown ether and four water molecules form bipyramidal structures which are stacked in layers alternating with the previous planes. © 1990 Kluwer Academic Publishers.