Photochemical Nitration by Tetranitromethane. Part XXXVII. Adduct Formation and the Regiochemistry of Attack of Trinitromethanide Ion on Radical Cations in the Photochemical Reactions of 2-Methyl-, 2,3-Dimethyl- and 2,4-Dimethylanisoles.
作者:Craig P. Butts、Lennart Eberson、Michael P. Hartshorn、Ward T. Robinson、David J. Timmerman-Vaughan、Lauri Niinistö、Stenbjörn Styring、Cecilia Tommos、Kurt Warncke、Bryan R. Wood
DOI:10.3891/acta.chem.scand.51-0073
日期:——
The photolysis of the charge transfer (CT) complex of tetranitromethane and 2-methylanisole 2 in dichloromethane at 20 degrees C gives the epimeric 1-methoxy-6-methyl-6-nitro-3-trinitromethylcyclohexa-1,4-dienes 8 and 9 in addition to 2-methyl-4-trinitromethylanisole (3) and 2-methyl-4-nitroanisole (4). In acetonitrile the yields of compound 4 and adducts 8 and 9 are significantly higher. Similar reaction of 2,3-dimethylanisole (6) in dichloromethane gave nitrotrinitromethyl adducts 10 and 11, hydroxy-trinitromethyl adducts 12 and 13, 2,3-dimethyl-5-trinitromethylanisole (14), 4-methoxy-2,3-dimethylbenzonitrile N-oxide (15), 2,3-dimethyl-4-trinitromethylanisole (16), 2,3-dimethyl-4-nitroanisole (17), 2,3-dimethyl-4,6-dinitrophenol (18), 3-methoxy-4,5-dimethyl-benzoic acid (19) and the hydroxy dinitro compound (20).The photolysis of the CT complex of 2,4-dimethylanisole (7) with tetranitromethane in dichloromethane gave the epimeric 1-methoxy-4,6-dimethyl-6-nitro-3-trinitromethylcyclohexa-1,4-dienes 21 and 22, together with 4,6-dimethyl-3-trinitromethylanisole (23), 4,6-dimethyl-2-nitrophenol (24), 4,6-dimethyl-2-trinitromethylanisole (25), 4,6-dimethyl-3-nitroanisole (26), 4,6-dimethyl-2-nitroanisole (27) and 4,6-dimethyl-4-nitrocyclohexa-2,5-dienone (28).The modes of formation of the above products are discussed, including the effects of the reaction solvent on those processes. The X-ray crystal structure of 1-methoxy-2-methyl-c-6-nitro-r-3-trinitromethylcyclohexa-1,4-diene (9) is reported.