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hA. N. Nesmeyanov Institute of Organoelement Compounds. Russian Academy of Sciences, 28 uL Vavilova, 117813 Moscow. Russian Federation. Fax: + 7 (095) 135 5085 h was found that the quantum yield of the fluorescence of meso-tetraferrocenylporphyrin Key words: meso-tetraferrocenylporphyrin, meso-tetraphenylporphyrin, ferrocene, fluorescence, nanosecond laser photolysis.The photochemical and photophysical properties of porphyrins have been studied in detail in development of photocatalytic processes and studies of electron transfer reactions in biological and artificial systems. I-6 Great attention was paid to porphyrin dyads and triads, molecular systems in which the tetrapyrrole cycle is covalently linked through a molecular bridge or without it with electron donors or acceptors such as viologen, quinones, C60, etc. 7-18 These molecularly organized systems imitate directed electron transfer in biological objects and are of interest for photocatalysis and devices that convert light energy into electric energy.New porphyrin molecules that can be considered as porphyrin dyads in which the tetrapyrrole cycle is covalently linked in the meso-position with metallocenes, in particular, with fcrrocene (FcH), directly tg.z~ or through various bridges, CHa--CHa, 21 trans-CH=CH 21 and eis-CH=CH, zl and -~O-were recently synthesized, z2,z3 A high quantum yield ofcha~e separation and efficient light conversion in photogalvanic cells were observed for the porphyrin linked with Fc through the phenoxyl bridge. ~ In this work, we studied the photochemical and photophysical properties of porphine covalently linked in meso-positions with four Fc groups, meso-tetraferrocenylporphyrin (TFcP). Quenching of singlet-and triplet-excited meso-tetraphenylporphyrin (TPP) by FcH was also studied to reveal the character of the interaction of excited porphine with Fc groups. ExperimentalThe following reagents were used: acetonitrile and toluene (Fluka, for HPLC analysis) as solvents, TPP (Fluka, without TFcP TPP additional purification), and ferrocene (Fluka). The latter was recrystallized four times from methanol lbllowed by vacuum sublimation. Synthesis of TFcP has been described in detail in previous works. 19"20

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