- Ultrafast photoinduced electron transfer in face-to-face charge-transfer π-complexes of planar porphyrins and hexaazatriphenylene derivatives
-
Charge-transfer (CT) π-complexes are formed between planar porphyrins and 1,4,5,8,9,12-hexaazatriphenylene (HAT) derivatives with large formation constants (e.g., 104 M-1), exhibiting broad CT absorption bands. The unusually large formation constants result from close face-to-face contact between two planar π-planes of porphyrins and HAT derivatives. The redox potentials of porphyrins and HAT derivatives measured by cyclic voltammetry indicate that porphyrins and HAT derivatives act as electron donors and acceptors, respectively. The formation of 1:1 CT complexes between porphyrins and HAT derivatives was examined by UV-vis, fluorescence and 1H NMR measurements in nonpolar solvents. The occurrence of unprecedented ultrafast photoinduced electron transfer from the porphyrin unit to the HAT unit in the CT π-complex was observed by femtosecond laser flash photolysis measurements. A highly linear aggregate composed of a planar porphyrin and an HAT derivative was observed by transmission electron microscopy (TEM) and atomic force microscopy (AFM).
- Aoki, Toru,Sakai, Hayato,Ohkubo, Kei,Sakanoue, Tomo,Takenobu, Taishi,Fukuzumi, Shunichi,Hasobe, Taku
-
p. 1498 - 1509
(2015/02/05)
-
- SYNTHESIS, STRUCTURE, AND PROPERTIES OF COMPOUNDS WITH A CHALCOGEN-NITROGEN BOND XIII. THE EFFECT OF THE NATURE OF THE CHALCOGEN ATOM ON THE ABILITY OF N-SULFONYLCHALCOGENIMIDES TO OXIDIZE HYDROQUINONE AND ITS DERIVATIVES
-
N-Sulfonyldiphenylsulfimides do not react with hydroquinone, 2,5-di(tert-butyl)hydroquinone, and tetrahydroxy-p-benzoquinone even with prolonged heating above 150 deg C.Selenimides and tellurimides with analogous structures oxidize these compounds to the corresponding quinones.The oxidizing power of the tellurimides in the investigated reations is higher than that of the selenimides.This is explained by the increased polarity of the chalcogen-nitrogen bond and, consequently, the ease of its cleavage in N-sulfonylchalcogenimides in the series: S Se Te.The intermediate products from the reaction of the tellurium derivatives with hydroquinone, i.e., polymeric diaryltellurium p-hydroxyphenolates, were isolated.
- Naddaka, V. I.,Avanesyan, K. V.,Cherkinskaya, M. L.
-
p. 705 - 711
(2007/10/02)
-
- The photochemistry of the rhodizonate dianion in aqueous solution
-
The photochemistry of the rhodizonate dianion at 483 nm has been studied in aqueous solution at pH 8.3.In the absence of oxygen no reaction was observed.In the presence of oxygen, 6.2 x 10-5 M, the dianion was consumed with a quantum yield of 0.044.The oxidation apparently did not involve the formation of O2(1Δg).Electron transfer from the excited dianion was observed with methyl viologen.
- Iraci, G.,Back, M. H.
-
p. 1293 - 1294
(2007/10/02)
-
- Synthesis and Some Reactions of Hexaazatriphenylenehexacarbonitrile, a Hydrogen-Free Polyfunctional Heterocycle with D3h Symmetry
-
In this paper, we report for the first time the synthesis of hexaazatriphenylenehexacarbonitrile, abbreviated HAT-hexacarbonitrile.This hydrogenless, symmetrically branched compound can be prepared in analytically pure form on a large scale by using commercially available starting materials.The conversions of HAT-hexacarbonitrile to the corresponding hexaamide, hexaacid, hexaester, and trianhydride derivatives were also accomplished.
- Kanakarajan, K.,Czarnik, Anthony W.
-
p. 5241 - 5243
(2007/10/02)
-
