Physicochemical insights in non-covalent interaction of a newly designed triporphyrin with fullerenes C60 and C70 in solution.

The present paper reports the synthesis of free-base (H(2)-1) and zinc-triporphyrins Zn-1, and their supramolecular complexes with C(60) and C(70) in toluene. While UV-Vis studies reveal ground state interaction between fullerenes and triporphyrins, steady state fluorescence measurements establish quenching of fluorescence of triporphyrins by fullerenes. Binding constants data evoke that Zn-1 may be employed as an efficient tweezers for C(70) in toluene. Time resolved emission studies establish relatively long-lived charge separated state for the C(70)/triporphyrin complexes. Molecular mechanics force field calculations in vacuo interpret the stability difference between C(60)/and C(70)/complexes of triporphyrin.