Oxidation of aryl-substituted cycloheptatrienes by photoinduced electron transfer
作者:Dirk Jacobi、Werner Abraham、Uwe Pischel、Lutz Grubert、R. Stösser、Wolfram Schnabel
DOI:10.1039/a902662b
日期:——
deaerated acetonitrile solution at room temperature to the corresponding radical cations is accomplished by electron transfer to the electronically excited acceptors 9,10-dicyanoanthracene (A2), N-methylquinolinium perchlorate (A3), N-methylacridinium perchlorate (A4), 2,4,6-triphenylpyrylium tetrafluoroborate (A5) and 1,1′-dimethyl-4,4′-bipyridinium dichloride (A6). In the case of 1 back electron transfer
室温下,在脱气的乙腈溶液中,芳基取代的环庚烯7-(对甲氧基苯基)环庚三烯(1a),7-,1-和3-(对二甲氨基苯基)环庚三烯(1b,1c和1d)发生光氧化。相应的自由基阳离子通过电子转移至电子激发的受体9,10-二氰基蒽(A2),N-高氯酸N-甲基喹啉鎓(A3),N-高氯酸甲基ac啶鎓(A4),四氟硼酸2,4,6-三苯基吡啶鎓(A5)和二氯化1,1'-二甲基-4,4'-联吡啶鎓(A6)。在1的情况下,反向电子转移并不重要。最初形成的自由基阳离子去质子化,并且所得的环庚三烯基自由基进行自反应,从而形成苄基。相反,1b,1c和1d仅非常轻微地分解,不形成二苯甲基,并且不消耗受体。