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Singlet oxygen photogeneration

As with other first-row transition metals, copper complexes are not expected to be satisfactory singlet oxygen photogenerators, because of the rapid deactivation of excited states in the presence of partially filled d-orbitals. The exceptional case of the copper(II) benzochlorin iminium salt ((18), M = Cu) has already been referred to (Section 9.22.5.6) this showed bioactivity, although the nickel(II) complex ((18), M = Nin) was inactive.195... [Pg.978]

Janczyk A, Krakowska E, Stochel G, Macyk W. Singlet oxygen photogeneration at surface modified titanium dioxide./ Am Chem Soc 2006 128 15574-5. [Pg.105]

Krasnovsky Jr, AA, Cheng P, Blankenship RE, Moore TA and Gust D (1993) The photophysics of monomeric bacterio-chlorophylls c and d and their derivatives Properties of the triplet state and singlet oxygen photogeneration and quenching. Photochem Photobiol 57 324-330... [Pg.338]

Photogeneration of singlet oxygen takes place at illumination of an 02-surrounded quartz surface with molecule-dispersed vanadium pentox-ide applied to the surface [93, 94]. A 10 - 10 molecule/cm concentration of 02( A ) in the gaseous phase can be obtained above a quartz... [Pg.305]

Thereby, photogeneration of singlet oxygen molecules from the quartz surface containing molecular dispersed molecules of pentoxide... [Pg.393]

The capability to photogenerate singlet oxygen is inherent not only to V205/Si02 systems but to several other non-organic heterogeneous... [Pg.394]

Similar to molybdenum oxide catalyst the capability to emit singlet oxygen is inherent to Si02 doped by Cr ions as well. Similar to the case of vanadium oxide catalysts in this system the photogeneration occurs due to the triplet-triplet electron excitation transfer from a charge transfer complex to adsorbed oxygen. [Pg.395]

It has been known for many years that ruthenium(II) complexes of non-macrocyclic ligands photogenerate singlet oxygen. Thus, in 1973 it was observed for [Run(phen)2(CN)2] that singlet... [Pg.972]

Ma J, Jiang L (2001) Photogeneration of singlet oxygen (102) and free radicals (Sen -, 02 -) by tetra-brominated hypocrellin B derivative. Free Radic Res 35 767-777. [Pg.104]

The reaction of photogenerated singlet oxygen with 2,5-dimethylthiophene results in ring opening (70TL791, 70TL795) the c/s-sulfine (149) and the rrans-diketone (150) are the main products. The mechanism of this reaction has been speculated upon. Since (149) itself is photoinert, the two products must arise by different pathways. The key intermediate is (148), formed by cycloaddition of the thiophene with 02 this can lead to the two observed products as shown in Scheme 28. An alternative pathway for the sulfine would be by attack of 02 on sulfur to yield (151), followed by the transformations shown. [Pg.768]

Nardello, V. and Aubry, J.-M. (2000) Measurement of photogenerated singlet oxygen in aqueous media. Methods in Enzymology, 319, 50—58. [Pg.381]

The proposed intermediacy of carbonyl ylides and their reactions with singlet oxygen are in accord with similar observations on trapping the photogenerated carbonyl ylides [164, 171-178]. [Pg.147]

Addition to 3,S-cyeloheptadiene-l-oi (1). Photogenerated singlet oxygen (hematoporphyrin hydrochloride, sensitizer) adds to 1 in a stereoselective manner isyn to OH) to give mainly the endoperoxide 2. The reaction of the acetate of 1 is less selective because the acetyl derivative of 3 rearranges readily under both photolytic and thermal conditions to a diepoxide. Under the same conditions the acetyl derivative of 2 is relatively stable. ... [Pg.175]

S.L. Holder Sandvik, P. Bilski, J.D. Pakulski, C.F. Chignell, R.B. Coffin (2000). Photogeneration of singlet oxygen and free radicals in dissolved organic matter isolated from the Mississippi and Atchafalaya River plumes. Mar. Chem., 69, 139-152. [Pg.279]

Triplet sensitization is the usual and most convenient means of generating singlet oxygen. Singlet oxygen is photogenerated from both ionized and unionized derivatives of triplet rose bengal and eosin Y in dilute solutions . The efficiency of... [Pg.31]

Scheme 8.1-4 The photogeneration of singlet oxygen by the ReAsH-tetracysteine complex and its use for CALI and photoconversion of diaminobenzidine (DAB). Scheme 8.1-4 The photogeneration of singlet oxygen by the ReAsH-tetracysteine complex and its use for CALI and photoconversion of diaminobenzidine (DAB).
See other pages where Singlet oxygen photogeneration is mentioned: [Pg.307]    [Pg.256]    [Pg.272]    [Pg.1287]    [Pg.307]    [Pg.256]    [Pg.272]    [Pg.1287]    [Pg.388]    [Pg.394]    [Pg.394]    [Pg.395]    [Pg.330]    [Pg.986]    [Pg.287]    [Pg.339]    [Pg.199]    [Pg.42]    [Pg.492]    [Pg.312]    [Pg.354]    [Pg.933]    [Pg.745]    [Pg.228]    [Pg.447]    [Pg.35]    [Pg.115]    [Pg.106]    [Pg.933]    [Pg.18]    [Pg.315]    [Pg.306]    [Pg.376]    [Pg.318]    [Pg.206]    [Pg.77]   
See also in sourсe #XX -- [ Pg.115 , Pg.266 , Pg.267 , Pg.268 , Pg.269 , Pg.270 ]



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Oxygenation singlet oxygen

Photogeneration

Photogenerators

Singlet oxygen

Singlet oxygenation

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