Pagodane and Its Derivatives

Unexpectedly, several of the pagodane derivatives possess rather low oxidation potentials, indicating a considerable thermodynamic stability of the one-electron oxidized stages, the radical cations. The oxidation potentials of pagodane derivatives are listed in Table 7.1. 

Pagodane Derivative First Oxidation Potential V versus Ag/AgCl 

UNUSUAL STRUCTURES OF RADICAL IONS IN CARBON SKELETONS 

FIGURE 7.4 Cyclovoltammograms of [l.l.l.l]pagodane and [l.l.l.l]pagodadiene versus Ag/AgCl (solvent, CH2CI2 supporting salt, tetrabutylammonium perchlorate). 

According to cyclovoltammetric investigations some of the derivatives possess even quasi-reversible oxidation waves although no extended n systems are present. This is illustrated in Fig. 7.4 for [l.l.l.ljpagodadiene. A first quasi-reversible redox process can be detected at 1/2 = 0.66 V versus Ag/AgCl resembling the formation of a persistent radical cation. 

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