Conformationally Controlled Gas-Solid Reactions

The scope of reactions of organic solids has been extended over the past decade to heterogeneous multi-phase systems. Here a crystalline solid is exposed to a gas or liquid with the expectation that the crystalline environment will dictate the stereochemistry of the products formed. For such reactions, model systems were chosen in our laboratories which are known to yield different products from different conformations in the dispersed phase. One may anticipate high selectivity for such reactions in the solid-state, for on crystallization the molecule will adopt a single conformation that will eventually determine the stereo-course of the reaction. 

Based on the above principle we provide the following examples (/) the elimination of some crystalline dihalogeno-adipates and dihalogeno-cyanobutanes with gaseous amines, ( ) the heterogeneous addition of bromine to crystalline ethylenes. 

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