Structure-Reactivity Relationship in Deoxycholic Acid Complexes

Structure-Reactivity Relationship in Deoxycholic Acid Complexes.—The three-channel motifs offer a variety of host-guest arrangements that may be exploited for the performance of solid-state reactions. Two kinds of reagents were occluded (a) peroxides, hydroperoxides, and peresters, which were activated thermally or by irradiation, (b) ketones, which were activated photochemically. 

The steroid H atom at 1 is the only hydrogen besides those at positions 5, and that appears to be available for the addition reaction in the a-type channel. However, the appropriate host-guest contact for addition to l , has, as yet, proved to be elusi e. Nevertheless, we have been able to direct the reaction to other sites by 

Popovitz-Biro, Ph.D. Thesis, Feinberg Graduate School, 1979. 

Leiserowitz, R. Popovitz-Biro, and C. P. Tang, to be published. 

According to the complexes investigated so far, the distances between the atoms directly involved in abstraction, namely O etone td Hsuroid between the atoms to be bonded, namely C gtone steroid atoms, range from 2.9—3.9 A and from 3.7—4.2 A, respectively. In these examples the angle between the C—H bond and the plane of the carbonyl system C =0 varies from approximately 55° to 90° (Table 4). Thus we are able to predict, with some certainty, the available steroid sites for reaction. According to Scheffer and Dzakpasu, solid-state intramolecular 

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