A convenient synthetic procedure of a series of polyyne-bridged porphyrin dimers from diphenylpolyyne dialdehydes is reported. Trichloroacetic acid catalyzed double condensation of diphenylpolyyne dialdehydes with bis(3-hexyl-4-methyl-2-pyrrolyl)methane and 3,5-di-tert-butylbenzaldehyde in acctonitrile-dichloromethane followed by p-chloranil oxidation gave a set of diporphyrin model compounds (Pn,
报道了从二苯基聚炔二醛中合成一系列聚炔桥卟啉二聚体的简便方法。三氯乙酸催化二苯基聚炔二醛与双(3-己基-4-甲基-2-吡咯基)甲烷和3,5-二叔丁基苯甲醛在丙烯腈-二氯甲烷中的双缩合,然后对氯苯醌氧化得到一套双卟啉模型由共轭三键桥接的化合物 (Pn, n = 0–4)。
Synthesis and Intramolecular Electron- and Energy-Transfer Reactions of Polyyne- or Polyene-Bridged Diporphyrins
A series of geometrically restricted polyyne- or polyene-bridged diporphyrins 1-7 has been prepared by a convenient, one-pot, double porphyrin cyclization reaction in acceptable yields from the corresponding dialdehydes 1-7CHO. Polyene-bridged diporphyrins 8 and 9 were prepared by a double Horner-Emmons-Wadsworth reaction of formyl-substituted zinc-porphyrin monomer 12 with bis-phosphonate esters 13 and 14, respectively. The diporphyrins 1-9 were transformed into zinc-free-base and zinc-ferric hybrid diporphyrins. Photoinduced intramolecular electron transfer in the zinc-ferric hybrid diporphyrins as well as intramolecular excitation energy transfer in the zinc-free-base hybrid diporphyrins have been studied by picosecond time-resolved fluorescence spectroscopy. Rate constants through the polyene-bridges are larger than those through the polyyne-bridges in both reactions. The distance dependence of the electron-transfer rate was found to be quite small: the attenuation factors were determined to be 0.08 and 0.1 Angstrom(-1) for the polyene- and polyyne-bridged diporphyrins, respectively. The distance dependence of the energy-transfer rate was quite similar to that of the electron transfer and was explained better by the Dexter mechanism rather than by the Forster mechanism. These results clearly demonstrate that the linear pi-conjugated polyyne and polyene spacers enhance through-bond electronic coupling between the donor and acceptor.
MARUYAMA, KAZUHIRO;KAWABATA, SHIGEKI, BULL. CHEM. SOC. JAP., 63,(1990) N, C. 170-175
作者:MARUYAMA, KAZUHIRO、KAWABATA, SHIGEKI
DOI:——
日期:——
Synthesis and Characterization of Polyyne Porphyrins
作者:Kazuhiro Maruyama、Shigeki Kawabata
DOI:10.1246/bcsj.63.170
日期:1990.1
A series of conjugated polyyne porphyrins, in which two porphyrin macrocycles are connected with both ends of diarylpolyyne through aromatic ring, has been prepared and their spectroscopic behaviors were investigated. Diarylpolyyne consisting of aryl group and conjugated triple bond system have rigid and linear structure, and the two porphyrins are held at a fixed geometry and a determined distance. In their absorption spectra, porphyrin Soret bands were red- or blue-shifted depending on their edge-to-edge or face-to-face orientation.