Acridinium dyes

At high concentrations in the absence of other more effective reductants, alcohols may act as activators of polymerization. Methyl methacrylate has been polymerized during irradiation of acriflavin, an acridinium dye, in methanol solution (79). The efficiency of the system was low. 

Several dyes have been found to sensitize the cationic polymerization of cyclohexene oxide, epichlorohydrin, and 2-chloroethyl vinyl ether initiated by diaryliodonium salts (109,110). Acridinium dyes such as acridine orange and acridine yellow were found to be effective sensitizers. One example of a benzothiazolium dye (setoflavin T) was also reported, but no other class of dye nor any other example of a dye absorbing at longer wavelengths were discovered. Crivello and Lam favored a sensitization mechanism in which direct energy transfer from the dye to the diaryliodonium salt occurred. Pappas (12,106) provided evidence that both energy transfer and electron transfer sensitization were feasible in this system. 

CO Acridinium Dye Q C60 Q Ti02 Nanoparticle OTE Optically Transparent Electrode Q Sn02... 

Typical photosensitizers for diaryliodonium salts are condensed ring aromatic hydrocarbons, diaryl ketones, and acridinium dyes. Condensed ring aromatic hydrocarbons are particularly effective photosensitizers for triarylsulfonium salts. The use of photosensitizers in onium salt photolysis permits the photoimaging processes induced by these compounds to be optimally fitted to the specific irradiation source used for their exposure. 

Quite a number of the classes of photoreducible dyes have been identified. These include the xanthenes (fluorescein, rose bengal), the thiazines (methylene blue, thionine), the acridinium dyes (acriflavin), and some natural products, such as riboflavin " ... 

Phosphine" [dye Cl 793, Chrysaniline mononitrate, 3-amino-9-(4-aminophenyl)-acridinium mononitrate) [10181-37-0] M 348.4, m >250°(dec), pKesi 8.0. Crystd from benzene/EtOH. 

When highly fluorescent ionic fluorophores, such as acridinium or xanthene dyes, are linked to a flexible electron-donor-substituted aryl group, a low-lying intramolecu-... 

Apocyanine dyes of the acridine series are obtained by treating acridinium iodide [43] or acridinium chloride [44] with tertiaiy aromatic amines. The dyes can also be obtained by ipso substitution of acridinium iodide with 4-haloaryl-amines in dimethyl sulfoxide at room temperature [45],... 

The family of photoreducible dyes (e.g, acridinium, xanthene, thiazinium among other classes of dyes) produce excited states of essentially quinoidal structures which can act as efficient acceptors of electrons. Amines [59], sulfur compounds, especially sulfmate salts [60], heterocycles of low ionization potential [61], alkylcarboxylates and stable enolate anions [62], and several classes of organo-metallic compounds, notably allylic and benzylic organostannanes [63], represent classes of compounds which have proved efficacious as coinitiators in electron transfer sensitization with these dyes. Electron transfer with the organometallics was unambiguously established in a series of model studies involving electron acceptors of the anthracene class [64],... 

In the only reversible approach [144], quatemized acridinium was immobilized on a solid support such as cellulose. In slightly alkaline medium, hydrogen sulflde adds to the strongly fluorescent dye and renders it nonfluorescent. Interferences by ionic quenchers may be eliminated by covering the sensor with a 4-pm silicone-rubber membrane which is permeable to gases but not to ions. The detection limit is of the order of 0.1 mmol L. ... 

Phosphine [dye Cl 793, Chrysaniline mononitrate, 3-amino-9-(4-aminophenyl)-acridinium mononitrate) [10181-37-0] M 348.4, m >250 (dec), pK 7.71 (50% aqueous EtOH). Crystallise the dye from benzene/EtOH. The free base crystallises from CgH6 in yelow crystals m 229-230". [Albert Goldacre J Chem Soc 709 1946, Beilstein 22 H 91, 22 1651, 22II403, 22 m/TV 5513.]... 

The spectrophotometric behaviour of solutions of 1-1 penta= methylene bis (3,6 - bis(dimethylamino) acridinium), D, was recently discussed D is a "Bifunctional or "dimer" dye obtained by con= necting the 10 - N nitrogens of two acridine orange (AO) molecules through a pentamethylene chain. 

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