A solvent-free organic synthesis from solid-state reactants through autogenous fusion due to formation of molecular complexes and increasing alcohol nucleophilicity

Crystalline imidazole (IM, mp 361-364 K) fuses autogenously immediately after making contact at room temperature with menthol (MT, mp 316 K) as a consequence of the hydrogen bond. Autogenous fusion is triggered by the recombination of the hydrogen bonds from the homogeneous ones (MT-MT) stabilizing MT crystals to the heterogeneous ones between OH of MT and N of IM to form an intermediate molecular complex at a eutectic composition. Formation of molecular complex parallels the increase in the nucleophilic affinity of MT by the intermolecular hydrogen bonds, as confirmed by the peak shift of H-1 NMR as well as by DFT computation. (c) 2006 Elsevier Ltd. All rights reserved.