A combined experimental and theoretical study addresses the concertedness of the thermal Curtius rearrangement. The kinetics of the Curtius rearrangements of methyl 1- azidocarbonyl cycloprop-2-ene-1-carboxylate and methyl 1-azidocarbonyl cyclopropane-1- carboxylate were studied by 1H NMR spectroscopy, and there is close agreement between calculated and experimental enthalpies and entropies of activation. Density functional ...
