TmPyP

Fig. 3. Haptens and multivalent antigens prepared in this syudy. The viologen derivative, 4,4 -bipyridinium, l-(carboxypentyl)-l -methyl-dichloride (1), divalent antigen 2, and trivalent antigen 3. Anti-porphyrin antibodies were elicited for [5-(4-carboxyphenyl)-10,15,20-tris-(4-methylpyridyl)]porphine (3MPylC) or meso-tetrakis(4-carboxyphenyl)porphine (TCPP). meso-Tetrakis(4-methylpyridyl)porphine (TMPyP) was used to investigate the specificity of the antibody dendrimer for porphyrins...

Fig. 11a,b. Binding affinities of IgG, IgM, and the antibody dendrimer (Gl) with the cationic porphyrin (TMPyP) (a) and those with the anionic porphyrin (TCPP) (b) estimated by ELISA... 

Electrocatalytic reduction of both O2 and H2O2 starts at potentials close to that of the Fe couple in the absence of a substrate (which for most porphyrins is about 0.2-0 V with respect to a normal hydrogen electrode (NHE) at pH < 6 the exception being Fe(TMPyP), E k 0.5 V). Catalytic reduction of H2O2 by simple/erne porphyrins is too slow to be detectable in typical electrocatalytic experiments whereas ferrous porphyrins catalyze rapid reduction of H2O2,... 

Water soluble iron porphyrins [Fem(TPPS)(H20) ]3-330 and [Fem(TMPy)(H20)2]5+ 331 332 (TPPS = maso-tetrakis(/ -sulfonatophenyl)porphyrin, TMPyP = / /e.vo-tetrakis(7V-methyl-4-pyridi-nium)porphyrin331 or maso-tetrakis (A -methyl-2-pyridinium)porphyrin332 dications) act as effective electrocatalysts for the reduction of nitrite to ammonia in aqueous electrolytes (Equation (64) Ei/2= 0.103 V vs. SCE at pH 7), with NH2OH or N20 also appearing as products depending on the reaction conditions. Nitric oxide then ligates to the iron(III) porphyrin to form a nitrosyl complex [Fen(P)(NO+)] (P = porphyrin) as intermediate. 

The electroreduction of NO to NH2OH and NH3 in aqueous media is also catalyzed by Mnin-TMPyP complexes.334 In contrast to the behavior found with iron porphyrin complexes, the reaction proceeds through an ECE mechanism, in which reduction of Mn111 to Mn11 is followed by NO coordination and then by electroreduction of [Mnn(NO)(TMPyP)]. 

Heavy metal ions detection with porphyrin in sol-gel is possible, too56. The porphyrin, used for detection of heavy metal ions (Hg2+, Pb2+, Cd2+), was 5,10,15,20-tetra(4-N-methylpyridil)porphyrin (TMPyP) preferred to other porphyrins because it was not leaked out of the matrix. The study of metallation of the porphyrin immobilized in sol-gel emphasized the formation of 1 1 complex for each ion with a constant of complexation depending on the nature of the ions. The strongest effects were observed for mercury due to the specific interaction of this metal with the porphyrin. 

TPPS = meso-tetrakis(p-sulfonatophenyl)porphine TMPyP = meso-tetrakis(A/ methyl-4pyridyl)porphine TMPS = meso-tetrakis(sulfonatomesityl)porphine... 

Iron(III)-TMPyP rapidly catalyzes the isomerization of ONO2 to NO3 (447) and the reaction also involves formation of an oxoFe(IV) intermediate. Iron(III)-TMPyP has been shown to have significant cytoprotective effects on cells both in vitro and in vivo and does not elevate mean arterial pressure suggesting a lack of interaction with NO (448). 

The use of the Co(I) porphyrin for the homogeneous electroreduction of dioxygen in DMF-BU4NC104-(C) system in the presence of benzoic anhydride has been developed [401]. The reduction of [(TMpyP)Co(II)]" + (where TMpyP = m o-tetrakis (1 -methylpyridinium-4-yl)... 

STM images of molecules are often a sensitive function of the tunnel conductance. For example, when examining TMPyP on Au( 111 )-I, the iodine underlayer was imaged at a tunnel resistance of 5 X 10 ohms while the electron density of TMPyP was observed at 8 X 10 ohms [484], Similar effects have been noted for protoporphyrins [488] and purines [489,490] adsorbed on graphite. 

The lack of retardation by added Fe(III) (tmpyp)OH on the rate of the Fe(II)tmpyp + (7) reaction with Oj indicates that Fe(III) porphyrin is not formed in the first step, i. e. (2.50) rather than (2.51) is the better description for the first step in the overall reaction ... 

Fig. 4.3 The dependence of the pseudo first-order rate constants upon anion concentration for the anation of Co(tmpyp)(H20) + by SCN at 15, 25, and 35°C in 0.1 M H +, p = 1.0 M." The solid lines conform to Eqn. (4.22). Reproduced with permission from K. R. Ashley, M. Berggren and M. Cheng, J. Amer. Chem. Soc. 97, 1422 (1975) (1975) American Chemical Society.

Fig. 37. Unusual hydroxylation with iron(III)TMPyP, 02, and NaBD ...

Exclusive enone formation could be achieved by electrocatalytic oxygenation of 2-cyclopentene-l-acetic acid in the presence of a water-soluble iron(III) porphyrin (2-TMPyP)Fe [2-TMPyP =tetrakis(N-methyl-2-pyridyl)porphyrin]. Unfortunately, neither yields nor TONs are given [116]. 

A recent contribution to the chemoselectivity problem is the composite photocatalysis developed by Maldotti et al. [117]. Cyclohexene la was subjected to photo-initiated oxidation in Nation membranes containing Pd(II) porphyrin Pd(4-TMPyP) [4-TMPyP = weso-tetrakis(N-methyl-4-pyridyl)porphyrin] and Fe(III) porphyrin 11 to... 

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