ISSN:
1573-1111
Keywords:
β-Dimorph
;
crystal structure
;
dianilinegossypol ethylacetate 1 : 1 clathrate
;
packing motifs
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
Notes:
Abstract Depending on crystallization conditions, dianilinegossypol and ethylacetate form low (ambient temperature, α-phase) and high temperature (t = 35°C, β-phase) clathrate modifications. The structure of the α-phase has been discussed earlier [1]. Crystals of the 1 : 1 β-phase complex, C42H40O6N2·C4O2H8, are monoclinic, space group P21/c, a = 11.362(6), b = 19.479(9), c = 19.085(9) Å, β = 103.21(4)°, V = 4112(3)Å3, Z = 4, R = 0.084 for 3210 observed reflections. In these complexes centrosymmetric dimers of dianilinegossypol molecules formed via O(5)—H···O(3) hydrogen bonds are associated into columns by a weak O(8)—H···O(7) H-bond. A difference in the structure of these two phases is in the packing mode of the columns. The angle formed by intersecting host columns is about 126° for the α-phase and 104° for the β-modification. Guest molecules are hydrogen bonded to the host molecules via an O(1)—H···O(10) bond and are accommodated in channels in α-phase complex and in cavities in β-phase complex.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1023/A:1007908530132
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