Phosphorescence of Cyclophanes and Cyclophane/Ag Complexes
نویسنده
چکیده
Phosphorescence in ethanol at 77 K. of the cyclophanes 1 1 4 has been investigated. It is shown that the phosphorescence characteristics are strongly determined by transannular interaction between the benzene rings. This interaction does not occur in cyclophanes 9 and 14. Phosphorescence quenching by silver Perchlorate of paracyclophanes and benzene derivatives 15-20 is due to the formation of arene/Ag ground state complexes. From the quenching data it is concluded that the complexes of paracyclophanes with Ag ions are more stable than the corresponding complexes of the benzene derivatives by approximately two orders of magnitude. Various factors are discussed regarding this marked difference in complex stability.
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