Tetrathiafulvalene porphyrin dyad

A tetrathiafulvalene (TTF)-porphyrin dyad (47) has been synthesized in which efficient PET occurs between the pendant TTF and the porphyrin, quenching the fluorescence of the latter and giving the system potential as a... 

Novel triads that contained tetrathiafulvalenes as electron donors and porphyrin chromophores (refer to previous section for porphyrin-fullerene dyads) as donor units have been recently reported [246] (Scheme 12). Improved analogs of the latter triads were soon considered by connecting the tetrathiafulvalene unit to a 7r-extended conjugated network [247]. 

For further information on synthesis, properties, and applications of pyrro-lidinofullerenes, the chiral representatives of which were generally prepared and used as racemates, we refer to a recent review by Prato and Maggini.214 Fields in which many fullerene-fused pyrrolidines have been studied are biological and medicinal chemistry351 and, above all, advanced materials science.352,353 In the latter context, dyads and triads used for photoinduced charge separation between a fullerene acceptor moiety and electron donors like porphyrins, tetrathiafulvalenes, ferrocenes, or polyenes, are worth particular mentioning.354-356... 

The porphyrin-TTF series was extended and the behavior of symmetric and asymmetric donor-acceptor systems evaluated. Novel symmetric porphyrin-te-trathiafulvalene-porphyrin triads annulated through quinoxaline linkers into planar and extended ji-conjugated molecules were synthesized and its behavior compared with porphyrin-tetrathiafulvalene dyads [231]. Cyclic voltammetry and spectro-electrochemical methods were utilized to elucidate the redox processes of both compounds. The first oxidation of the triad in the peripheral porphyrin sites was followed by the formation of TTF radicals, but this sequence was reversed in the corresponding dyad. Ab initio calculations were realized demonstrating that TTF-type and porphyrin-type HOMOs have similar energies thus explaining that behavior. 

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