Enhancement of a Chemical Reaction Rate by Proper Orientation of Reacting Molecules in the Solid State

Efforts to understand catalytic enhancement of chemical reaction rates have often been aided by attributing orienting and proximity-inducing properties to the catalysts.¹ Given the knowledge that proper orientation and proximity facilitate chemical reaction, chemists have looked to the crystalline state for situations in which particularly reaction-favorable molecular relationships might be found.² However, although many reports exist of topochemical control of product formation selectivity,³ we have been unable to find an example in the literature (outside the polymerization area) of a solid-state accelerated thermal reaction. We now wish to report the identification of such a process, along with an X-ray diffraction study of the compound involved which shows that the molecules are nearly ideally oriented for reaction in the solid state.