Zinc tetraphenylporphyrin ZnTPP

Becker et al. (1985 a) also investigated the photolytic dediazoniation of arenediazonium salts sensitized by zinc tetraphenylporphyrin (ZnTPP). Due to the very different lifetimes of singlet and triplet ZnTPP (1.8 ns and 1.4 ms, respectively) it is possible to differentiate between singlet and triplet electron transfer reactions using different diazonium salt concentrations. 

In spite of the potentialities of reversed micelles entrapping nonaqueous highly polar solvents [34], very few investigations on the solubilization in such systems are reported in the literature. An example is the study of the solubilization of zinc-tetraphenylporphyrin (ZnTPP) in ethylene glycol/AOT/hydrocarbon systems by steady-state and transient... 

Prisner et al. measured the time dependence of CIDBP spectra in the photooxidation of zinc tetraphenylporphyrin (ZnTPP, SxlO" M) with duroquinone (DQ, 5x10 M) in ethanol at -28 °C with FTBSR [17]. The observed spectra are shown in fig. 5-8. Here, the signals with sharp HFS are due to DQ and the underlying broad ones are due to ZnTPP . 

Fig. 1 Stability constants of neutral nitrogen ligands with zinc tetraphenylporphyrin (ZnTPP) as a function of piCa of the conjugated acid pyridines, x imidazole, aliphatic amines, A o-substituted pyridines...

The above method extends the number of indicators available for oxygen sensor. In this section, we describe some examples to use the new systems using Ti-T absorption quenching for oxygen concentration measurement, such as zinc tetraphenylporphyrin (ZnTPP) [67] and fullerene C o immobilized in a polystyrene (PS) film [68]. 

In this review, we restrict ourselves to metal-mediated assemblies of functional 7T-systems, which absorb light in the visible region (i.e. A. > 400 nm). Thus, materials whose color arises from metal ions or metal-ligand charge transfer (MLCT) are not included here. Self-assembhes derived from free base porphyrins, metalloporphyrins and perylene bisimide dyes have shown promising applications in artificial LH systems. Therefore, some fundamental properties of a few representative chromophores, namely meso-tetraphenylporphyrin (TPP), zinc tetraphenylporphyrin (ZnTPP), tetra-phenoxy-substituted perylene bisimide (PPBI) and bay area imsubstituted perylene bisimide (PBI), are briefly summarized herein. These properties are essential for the understanding of the photophysical and photochemical behavior of assemblies derived from such dyes. 

Zinc tetraphenylporphyrin (ZnTPP) has been used recently as a model compound for Sj spectroscopic and dynamics studies, and has been the subject of intensive study. Some interesting questions regarding the actual relaxation mechanism stiU remain, however. Gurzadyan et al. recorded the Sj fluorescence decay and the Sj fluorescence rise profiles of ZnTPP in ethanol solution by fluorescence upconversion at an excitation wavelength of 394 run [119], In their experiment, the Sj state decayed exponentially with a 2.35 ps lifetime, identical to the risetime of its Sj fluorescence. A 60-90 fs rise component in the S 2 fluorescence profile was ascribed to IVR in the S2 state. Gurzadyan and coworkers also showed that Xjj for ZnTPP... 

The design of a system for photoswitching on and off coordination sites in a self-assembled mono-layer (SAM) containing an azopyridine unit has recently been reported by Cook and co-workers. The required SAM was prepared by depositing an unsymmetrical disulfide 28 having 4-(arylazo)pyridine and phenoxy moieties onto an 8-nm-thick film of gold supported on a quartz glass slide. Scheme 64 outlines the system for the evanescent field-driven SAM photoswitch. Zinc tetraphenylporphyrin (ZnTPP) was... 

Zinc-5,10,15,20-tetraphenylporphyrin (ZnTPP) has been used as a coating material in ammonia sensors by immobilizing it on the surface of silicone rubber. Absorbance and fluorescence emission were the modes of detection. A spectral change is caused by the coordination of NH3 molecules to the Zn11 ion in the immobilized metalloporphyrins. Sensing films made from the ZnTPP immobilized in silicone rubber were found to be the most sensitive for NH3 sensing (20). 

A number of workers have studied zinc tetraphenylporphyrin complexes, and an intensive study of the luminescence properties of [ZnTPP] has been reported.1180 [ZnTPP] is also used in the well-known synthetic leaf experiments.11806... 

NADH Nicotineamide adenine dinucleotide reduced form. EDTA Ethylenediamine tetraacetic acid. RSH Mercaptoethanol. ZnTPP Zinc tetraphenylporphyrin. ZnTMPyP Zinc tetrakis(4-methylpyridyl)porphyrin. ZnTPPS Zinc tetraphenylporphyrin tetrasulfomate. 

Zinc(II) tetraphenylporphyrin (ZnTPP) can be covalently incorporated into the unimer micelle by terpolymerization using a ZnTPP-substituted acrylamide monomer Zinc(Il) S(4-acrylamidophenyl)-10,15,2(ftriphenylporphynate (ZnAATPP) (Chart 4) (56). The ZnTPP units compartmentalized within the hi er-order unimer micelle are protected from the bulk aqueous phase. Because the amount of the ZnTPP units incorporated in the terpolymers are very small (0.1-0.2 mol %), each ZnTPP unit is independently compartmentalized in the hydrophobic microdomain and is prohibited from encountering otheiB. In the reference copolymer (Chart 4), on the other hand, the ZnTPP moieties are exposed to the aqueous phase. 

---