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Zinc complexes porphyrin

The design of dendritic multiporphyrin systems [18] permits energy transfer over longer distances. The outer shell of the dendrimer shown in Fig. 5.14 is made up of eight porphyrin-zinc complexes as energy donor units. Excitation of the units of the outer shell leads to fluorescence emission of the metal-free porphyrin core as a result of energy transfer from the periphery to the energy acceptor [19]. [Pg.183]

Fig. 6.51 Dendritically linked porphyrin/zinc complexes with fullerene at the focal point (according to Aida et al.)... Fig. 6.51 Dendritically linked porphyrin/zinc complexes with fullerene at the focal point (according to Aida et al.)...
The interesting dual behaviour of porphyrin derivatives is demonstrated by intramolecular electron transfer between an electron-rich tris(4-methylphenyl)porphyrin zinc complex (ZnTPP) and an electron-deficient tris(4-methylphenyl)octafluoroporphyrin (TPOFP) (Teflon porphyrin) free base connected via an azobenzene moiety (438 Scheme 6.209).1250 Upon photolysis at >440 nm, E —> Z photoisomerization (Section 6.4.1) occurs. (Z)-438 can revert to ( )-438 only thermally, because the excited state of the Z-isomer is efficiently quenched by intramolecular electron transfer from ZnTPP to TPOFP, whereas no such interaction is possible in the -isomer because the chromophores are too remote. This approach has been suggested for photocontrolled molecular electronics. [Pg.379]

Subsequent related work by Hayashi, Ogoshi and coworkers then served to show that rapid ET can also be achieved by use of aaaa-/weso-tetrakis(2-hydroxy-l-naphthyljporphyrin zinc complex (122) and aaoLOL-meso-tetrakis(7-hydroxy-l-naphthyl)porphyrin zinc complex (123).The.se affinities for TMBQ were determined, by titrimetric measurement of visible spectra, to be... [Pg.314]

Modulation of vectorial energy transfer in the telrakis[tris(bipyridine) ruthenium(It)]porphyrinate zinc complex. J. Photochem. Photobiol. A 142, 25-30. [Pg.309]

Porphyrin, octaethyl-, zinc complex cyclic voltammetry, 4, 399 <73JA5140)... [Pg.42]

Porphyrin, tetrahydro-metal complexes geochemistry. 6, 862 Porphyrin, tetraphenyl-indium complexes radiopharmacology, 6, 971 iron complexes, 4, 260,1266 zinc complexes spectra, 6, 617... [Pg.202]

H NMR data has been reported for the ethylzinc complex, Zn(TPP—NMe)Et, formed from the reaction of free-base N-methyl porphyrin H(TPP—NMe) with ZnEti. The ethyl proton chemical shifts are observed upheld, evidence that the ethyl group is coordinated to zinc near the center of the porphyrin. The complex is stable under N2 in the dark, but decomposed by a radical mechanism in visible light.The complex reacted with hindered phenols (HOAr) when irradiated with visible light to give ethane and the aryloxo complexes Zn(TPP—NMe)OAr. The reaction of Zn(TPP—NMe)Et, a secondary amine (HNEt2) and CO2 gave zinc carbamate complexes, for example Zn(TPP—NMclOiCNEti."" ... [Pg.312]

The functionalization of zinc porphyrin complexes has been studied with respect to the variation in properties. The structure and photophysics of octafluorotetraphenylporphyrin zinc complexes were studied.762 Octabromoporphyrin zinc complexes have been synthesized and the effects on the 11 NMR and redox potential of 2,3,7,8,12,13,17,18-octabromo-5,10,15,20-tetraarylporphyrin were observed.763 The chiral nonplanar porphyrin zinc 3,7,8,12,13,17,18-heptabromo-2-(2-methoxyphenyl)-5,10,15,20-tetraphenylporphyrin was synthesized and characterized.764 X-ray structures for cation radical zinc 5,10,15,20-tetra(2,6-dichlorophenyl)porphyrin and the iodinated product that results from reaction with iodine and silver(I) have been reported.765 Molecular mechanics calculations, X-ray structures, and resonance Raman spectroscopy compared the distortion due to zinc and other metal incorporation into meso dialkyl-substituted porphyrins. Zinc disfavors ruffling over doming with the total amount of nonplanar distortion reduced relative to smaller metals.766 Resonance Raman spectroscopy has also been used to study the lowest-energy triplet state of zinc tetraphenylporphyrin.767... [Pg.1216]

Dinaphthotetraazaporphyrins are structural isomers of phthalocyanines. The zinc complex was formed and the properties compared to zinc phthalocyanines demonstrating a lower fluorescence quantum yield for the zinc-fused naphthalene porphyrin (D2h symmetry) vs. the zinc phthalocyanine (D4h)S36... [Pg.1221]

Several reports of carboranylated porphyrins have appeared for utilization in the BNCT of cancer.150 The examples include both nido- (126) (Fig. 73) and closo-carborane cluster-containing (124 and 125) (Fig. 73) materials. Metal-free nido-carboranylporphyrins were able to deliver a higher amount of boron to cells than the corresponding zinc complexes. [Pg.74]

This section describes that the first example of photoenhanced copolymerizability of epoxide and episulfide in a reaction using the zinc complex of M-substi-tuted porphyrin (NMTPP)ZnSPr (17,X=SPr) as initiator. [Pg.110]

The metallation of TPPH2 in D20 or H20 has been studied, and the rate difference (kn/kD = 2.3) shown to be due to differences in the concentration of OH and OD complexes, and not due to intrinsic differences in the reactivity of TPPH and TPPD.1149 The synthesis and properties of porphyrins bearing cationic or anionic substituents are areas of active interest, and zinc complexes of the ligands (172), tetrabenzoporphyrin and octamethylporphyrin have been studied.1150-1154... [Pg.994]

A number of studies concerning zinc complexes of porphyrins or related ligands have also been reported 1193-1196 cadmium complexes of a number of porphyrins have also been investigated,1197-1199 a number of NMR studies of zinc porphyrin complexes have been made1200,1201 and a number of donor-acceptor complexes of zinc tetrapyrrole species with 1,3,5-trinitrobenzene have been described.1202 Recent developments in metallo-phthalocyamine chemistry, including aspects of zinc complexes, have been reviewed.9-15,12026,1468 11... [Pg.996]

Another example of compounds with the fixed mutual location of porphyrin and quinone are the porphyrin-quinone compounds with a rigid bridge. Charge photoseparation in P-L-Q molecules in which L is the trip-ticene bridge, P is tetraphenylporphin, TPP, or its zinc complex, and Q is benzoquinone, BQ, naphthoquinone, NQ, or anthraquinone, AQ, has been studied [55]. The distance between the centres of P and Q fragments in these... [Pg.332]

We would like to thank Dr. W. S. Caughey for providing the porphyrin-zinc(II) complexes. [Pg.69]

From these measurements the resonance positions in ferrocytochrome c of the protons corresponding to the hyperfine-shifted lines in ferricytochrome c are obtained. Gupta and Redfield (123) found that one of the ring methyl resonances of heme c is shifted upfield by ca. 1.5 ppm, indicating close proximity to the face of an aromatic amino acid residue in the reduced cytochrome c. The resonance positions in ferrocytochrome c are probably a better approximation of the diamagnetic heme resonance positions in ferri cytochrome c than are the porphyrin-zinc (II) complexes (Fig. 9). Hence experiments of this type could conceivably contribute towards a more accurate determination of the spin density distribution in the heme groups. [Pg.117]

Tris(4-isopropylphenyl)-20-(4-methacryloyl-oxyphenyl)porphyrine zinc(II) complex... [Pg.186]


See other pages where Zinc complexes porphyrin is mentioned: [Pg.1217]    [Pg.244]    [Pg.5189]    [Pg.5188]    [Pg.247]    [Pg.343]    [Pg.1217]    [Pg.244]    [Pg.5189]    [Pg.5188]    [Pg.247]    [Pg.343]    [Pg.202]    [Pg.219]    [Pg.229]    [Pg.633]    [Pg.1217]    [Pg.1217]    [Pg.1217]    [Pg.1220]    [Pg.394]    [Pg.980]    [Pg.995]    [Pg.114]    [Pg.7]    [Pg.218]    [Pg.653]    [Pg.601]    [Pg.105]    [Pg.207]    [Pg.207]    [Pg.411]    [Pg.154]    [Pg.332]    [Pg.94]    [Pg.176]   
See also in sourсe #XX -- [ Pg.993 ]




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