Long distance-SRN1 in nitroimidazole series favored by temperature

New reductive alkylating agents in 4- and 5-nitroimidazole series produce exclusively O-alkylation with nitronate anions under classical SRN1 conditions at room temperature. Electron-transfer C-alkylation is observed under microwave irradiation or under conventional heating. Furthermore, X-ray spectroscopy shows that the dihedral angles between the phenyl and imidazole rings for the two series are different, which could greatly influence reactivity in 4- and 5-nitroimidazole series.