Polymorphism of Inclusion Complexes and Unsolvated Hosts. I. Trimorphism of the Host-Guest Complex of Gossypol with Dichloromethane. The Structure of the β-Phase

The formation of host-guest complexes of gossypol at different temperatures has been investigated for the same pressure and concentration. Gossypol forms three different clathrates with dichloromethane within the temperature interval of 22-36 °C. Single crystals of these three modifications (phases) were obtained and their crystallographic parameters measured. The structure of the α-phase has been determined previously and the γ-phase is isostructural to the inclusion complex of gossypol with benzene, while the structure of the β-phase has been solved during the present research. Crystals of C30H30O8·CH2Cl2 are triclinic, space group P1, a = 8.604(1), b = 11.858(2), c = 14.405(2) (A), α = 84.60(1), β = 89.14(1), γ = 89.73(1)°, V = 1463(1) A3, Z = 2, R = 0.089 for 2419 observed reflections.