Site Selective Processes: A Combined Theoretical and Experimental Investigation of Thermally Activated Tautomerization Processes in 2(2,4-Dinitrobenzyl) Pyridine Derivatives

The thermally activated NH→CH tautomerization process in crystals of 2(2,4-dinitrobenzyl) pyridine derivatives was investigated. The results indicate the absence of any trivial molecular structure–reactivity correlation, in contrast to what is found for similar systems in solutions. The absence of molecular structure–reactivity correlation in the crystalline state is attributed to the participation of neighboring molecules in the proton transfer process. A combined experimental and theoretical approach is presented and applied to the study of the tautomerization reaction in crystalline environments.