Vyacheslav Diev - Fused pyrene-diporphyrins: shifting near infrared absorption to 1.5 mm and beyond

Version 1

      Publication Details (including relevant citation   information):

      Angew.   Chem. Int. Ed.   2010, 49, 5523-5526.

      Abstract:

      The prepn. of a new class of diporphyrin-

      pyrene hybrid compds. via a relatively simple method is reported.   The key step is the oxidative ring closure of the pyrene with the   porphyrin core. Pyrene-substituted zinc porphyrin fused dimer I   (Ar = 3,5-di-tert-butylphenyl) was prepd. in two steps (Suzuki   coupling and Osuka's oxidative fusion of porphyrin rings)   starting from a disubstituted zinc metalloporphyrin. Double   fusion of two pyrene rings with the diporphyrin moiety to give II   (M = H2, same Ar) is accomplished with anhyd. FeCl3 in CH2Cl2.   This crude product can be readily metalated to afford II (M = Zn,   Pb). The direct fusion of arom. rings to porphyrins occurred   without the need to activate porphyrin rings with nickel, or the   arom. rings with alkoxy groups. The UV-visible-NIR spectra of I   and II (M = H2, Zn, Pb) were studied, and their redox potentials   were detd. by cyclic voltammetry. Thin films of II (M = H2, Zn,   Pb) contg. different ratios of [6,6]-phenyl-C61-butyric acid Me   ester (PCBM) were prepd. and noncovalent interactions between the   porphyrins and π-conjugated acceptors were studied by   UV-visible-NIR spectroscopy. Pyrene-fused dimers II were used as   active materials in NIR photodetectors, and give external quantum   efficiencies of ≤ 6.5% at λ = 1350 nm for II (M = Zn). The effect   of arom. ring fusion to porphyrin tapes in a (meso,β) mode was   also explored by DFT methods for several diporphyrin core   systems.

      Address (URL): http://onlinelibrary.wiley.com/doi/10.1002/anie.201002669/abstract