PHOTOCHEMICAL NITRATION BY TETRANITROMETHANE .17. THE REGIOCHEMISTRY OF ADDUCT FORMATION IN THE PHOTOCHEMICAL-REACTION OF 1-METHYLNAPHTHALENE AND TETRANITROMETHANE

Photolysis of the 1-methylnaphthalene/tetranitromethane charge-transfe r complex yields the triad of 1-methylnaphthalene radical cation, nitr ogen dioxide and trinitromethanide ion. Recombination of this triad gi ves predominantly -2-nitro-r-1-trinitromethyl-1,2-dihydronaphthalene ( 1), the epimeric l-1-nitro-4-trinitromethyl-1,4-dihydronaphthalenes (2 ) and (3), yl-c-4-trinitromethyl-1,4-dihydronaphthalen-r-1-ol (4), nit ro cycloadduct (5), yl-c-4-trinitromethyl-1,4-dihydronaphthalen-r-1-ol (6), hydroxy cycloadduct (7) and yl-t-1-trinitromethyl-1,2-dihydronap hthalen-r-2-ol (8). Adducts (1)-(3), (5), (7) and (8) are formed by at tack of the trinitromethanide ion at C4 of the 1-methylnaphthalene rad ical cation, while adducts (4) and (6) are formed by corresponding att ack at C5. Adduct (1) undergoes thermal cycloaddition to give the nitr o cycloadduct (5) and it is assumed that the hydroxy cycloadduct (7) i s formed in analogous manner from yl-t-1-trinitromethyl-1,2-dihydronap hthalen-r-2-ol (8). X-Ray crystal structure determinations are reporte d for adducts (1), (3)-(5) and (7).