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Nitration of methyl salicylate was performed by ferric nitrate in refluxing ethyl acetate solution. A coordination-mediated radical nitration process was proposed based on the results of electronic absorption spectra, cyclic voltammetry and electrospray ionization mass spectra. It was the coordination of methyl salicylate with ferric nitrate that promoted the splitting of NO bonds of nitrate group in ferric nitrate and resulted in the formation of nitro radicals, oxygen radicals and complex radicals. The nitro radicals reacted with methyl salicylate or its complexes with iron to give a series of nitration products and Fe(II) ions. Meanwhile, oxygen radicals hydrolyzed to hydroxide which precipitated free ferric ions to isolate solid ferric oxides.

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Five representative coal samples used for coking were carbonized in a thermogravimetric analyzer to simulate an industrial coking process. The gaseous organic compounds generated were analyzed with a coupled mass spectrometer. During coal carbonization, thermal detachment of aliphatic side groups causes disintegration of the coal structure. Methyl groups detach at higher temperatures than methylene and methine groups, and the temperatures corresponding to peak generation of these groups increase with the metamorphic grade of the coal. Methane is generated by three mechanisms: below 370 °C, methane adsorbed in coal is thermally released; at about 510 °C, methyl groups are thermally detached from the coal to form CH3+ ions, which further combine with hydrogen to form methane; finally, at about 720 °C, methane is produced as a result of the condensation of aromatic rings to form larger fused rings. Benzene is also generated by three mechanisms: at 400–500 °C, aromatic structures in coal lose side groups (e.g. methylene or methine) to form benzene ions, which subsequently react with hydrogen to form benzene; at 500–700 °C, benzyl structures in coal lose methyl groups to form benzene ions, which then combine with hydrogen to form benzene; finally, at about 800 °C, condensation of fragments in coal also forms benzene.

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