106117-28-6Relevant articles and documents
A novel synthetic route to sapphyrins
Paolesse, Roberto,Licoccia, Silvia,Spagnoli, Mariangela,Boschi, Tristano,Khoury, Richard G.,Smith, Kevin M.
, p. 5133 - 5137 (1997)
New methodology has been developed for the synthesis of so-called sapphyrins, pentapyrrolic 'expanded porphyrins'. An efficient approach involving acid-catalyzed condensation of 1,19-diunsubstituted a,c-biladienes and 3,4-dialkylpyrrole-2-carbaldehydes eliminates the preparation of bipyrrolic intermediates and allows the synthesis of sapphyrins with an unsymmetrical array of peripheral substituents. The β-substitution pattern of 2,3,13,17-tetraethyl-7,8,12,18,22,23-hexamethylsapphyrin has been unambiguously confirmed by single crystal X-ray crystallography. 1H NMR spectra of the dication salts of sapphyrins are strongly dependent upon the counterions, and the pattern of resonances observed in solution is related to the stacking interactions between the macrocycles.
Dissociation kinetics of copper and cobalt complexes with sterically distorted porphyrins
Kuvshinova,Kuz'min,Dudkina,Pukhovskaya,Semeikin,Golubchikov
, p. 133 - 136 (2002)
The dissociation kinetics of the cobalt and copper complexes with octaethylporphyrin, its 5-phenyl, 5,15-diphenyl, and 5,10,15,20-tetraphenyl derivatives, and dodecaphenylporphyrin in acetic acid with small additions of trifluoroacetic acid were studied. In this series of complexes, the steric distortion of the tetrapyrrole macrocycle sequentially increases, which results in a regular decrease in the kinetic stability of the metal porphyrins: The dissociation rate increases by three orders of magnitude.
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Paine III et al.
, p. 3857,3859 (1976)
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Der Einbau von Magnesium in Liganden der Chlorophyll-Reihe mit (2,6-Di-t-butyl-4-methylphenoxy)magnesiumjodid
Zass, Engelbert,Isenring, Hans Peter,Etter, Rolf,Eschenmoser, Albert
, p. 1048 - 1067 (1980)
Experimental details are given for the new method of introducing magnesium into porhpinoid ligands by (2,6-di-t-butyl-4-methylphenoxy)magnesium iodide (1), previously published in preliminary form .Besides magnesium octaethylporphyrinate (14), methyl pyrochlorophyllide a (10), methyl chlorophyllide a (8), and methyl bacteriochlorophyllide a (12), the complexation of pheophytin a (2) to chlorophyll a (3) and of pheophytin b (4) to chlorophyll b (5) are described.
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Inhoffen et al.
, p. 1141 (1969)
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Johnson,Dolphin
, p. 2197,2198 (1976)
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Whitlock,Hanauer
, p. 2169 (1968)
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Wang,Chang
, p. 548 (1979)
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Phenyl-substituted porphyrins. 1. Synthesis of meso-phenyl-substituted porphyrins
Syrbu,Lyubimova,Semeikin
, p. 1262 - 1270 (2004)
A method was developed for the synthesis of a series of meso-phenyl-substituted octaalkylporphyrins with various numbers of phenyl groups at various positions. Some of their properties were studied.
Metalloporphyrin mixed-valence π-cation radicals: Solution stability and properties
Brancato-Buentello, Kristin E.,Kang, Seong-Joo,Scheidt, W. Robert
, p. 2839 - 2846 (1997)
Solution equilibria and optical spectra of several metallooctaethylporphyrin π-cation radicals have been examined in methylene chloride solution. The several π-cation radical species, [M(OEP.)]Y (M = Cu, Ni, Zn, Pd, or VO; Y = ClO4- or SbCl6-), are found to dimerize to form [M(OEP.)]22+. These dimeric species are characterized by the appearance of a new, strongly concentration-dependent near-infrared absorption band. This band is found in the region of 900-960 nm for all compounds except for the vanadyl complex which absorbs farther to the red at 1375 nm. The equilibrium constants for the dimerization reaction (2[M(OEP.)]+ (K(D)) [M(OEP.)]22+) have been evaluated from multiple-wavelength, concentration-dependent absorption data. Equimolar solutions of these π-cation radicals and their analogous neutral M(OEP) derivatives react to form new binuclear species, [M(OEP(./2)]2+, in which the single radical electron is delocalized over both porphyrin rings. These new species, for which we suggest the term 'mixed-valence' π-cation radical and which bear a formal relationship to the oxidized special pair of photosynthetic reaction centers, also display a near-infrared absorption band. The near-IR band is however distinctly different from that of the π-cation radical dimers. Equilibrium constants for the formation of these new species (M(OEP) + [M(OEP.)]+ (K(MV)) [M(OEP(./2)]2+), have also been determined. The values of K(MV) are 10-100-fold larger than the analogous dimerization constant K(D). Values of ΔH and ΔS have been obtained for both equilibrium processes. The variations in K(MV) and K(D) values are largely the consequence of entropy differences that probably result from a much stronger solvation of the π-cation radical compared to the neutral porphyrin.
The exhaustive reduction of formylporphyrins to methylporphyrins using dimethylformamide/water as reductant under microwave irradiation
Fletcher, Sarah J.,Harper, Shannon R.,Arnold, Dennis P.
, p. 200 - 208 (2014/05/20)
The reduction of meso-formyl derivatives of 5,15-diaryl- and 5,10,15-triphenylporphyrin (and their nickel(II) complexes) to the corresponding meso-methyl porphyrins is achieved in high yield by microwave heating of the substrate in dimethylformamide (DMF)
