Reineckate ion

An actinometer is a device used to measure the number of einsteins emitted at a particular wavelength by a particular light source. Photon-counting devices are now available and secondary chemical actinometers have been developed, such as that based on the Reineckate ion, Cr(NH3)2(NCS)4 , as... 

For drugs, liquid and polyvinyl chloride membrane electrodes which are sensitive and selective for atropine have been described. They are based on the inclusion of an atropine-reineckate ion-pair complex in the PVC matrix . ... 

Amin and Issa [15] described an indirect atomic absorption spectrometric method for the determination of primaquine and other antimalarials. The method is based on the formation of their ion-associates with [Cd2+, Co2+, Mn2+, and Zn2+1] thiocyanate, ammonium reineckate, and/or sodium cobaltinitrate. 

W.R. Jones, C. Haber and J. Reineck, Paper Presented at the International Ion Chromatography Symposium 1994, Turin, Italy, 1994, Paper no. 56. 

Liu et al. have reported the development and applications of the commonly used local anaesthetic sensitive field-effect transistor(FET) [56]. The ion-pair complexes of procaine with silicotungstate, tetraphenylborate, or reineckate were prepared as electroactive materials for a drug sensor. These active materials were coated onto the platinum draw wire of a MOSFET to make a local anaesthetic-sensitive FET that... 

Shen et al. have reported studies on procaine-selective electrodes embodying PVC membranes [57]. Various ion-pair complexes (procaine derivatives with tetraphenylborate, dipicrylamine, tetraiodomecurate, and reineckate) were incorporated into platinized PVC membranes, and with dinonyl phthalate as the solvent mediator, formed procaine selective electrodes. The efficiency and performance of these were compared, and it was found that procaine picrylamine and procaine tetraphenylborate were the best electroactive materials. The procaine picrylamine electrode exhibited a Nemstian response over the range 10 pM to 0.1 M, and was used as the indicator electrode for the potentiometric determination of procaine. The method recovery was found to be 99.8%, with a standard deviation of 0.9%. 

Hassan and Rizk developed potentiometric dipyridamole sensors based on lipophilic ion-pair complexes and native ionic polymer membranes [18]. The sensors are based on the use of the ion-association complexes of dipyridamole cation with tetraphenylborate and reineckate counteranions as ion-exchange sites in plasticized PVC matrices. A plasticized native polymer (carboxylated polyvinyl chloride) can also be used. These sensors exhibit linear and near-Nernestian responses for 10 mM-1 pM... 

Fresh plants extracted with CH3OH were purified by ion exchange chromatography, and crystallisation as Reineckate and again ion exchange chromatography yielded 6 x 10 % as chloride... 

A number of strategies for the photochemical initiation of anion or cation catalyzed polymerization have been explored. For example, visible photolysis of the Reineckate anion, [Cr(NH3)2(NCS)4], has long been known to release a thiocyanate ion. Photolysis of the Reineckate anion in the presence of ethyl cyanoacrylate initiates polymerization. The release of acac anions, and benzoylcyclopentadienyl... 

Thus, upon irradiation of an aqueous reineckate solution with visible radiation between 316 and 750 nm the release of one or more thiocyanate ions is observed with a quantum yield of O = 0.3. The photogenerated thiocyanate can easily be quantified spectrophotometrically at 450 nm as its Fe (SCN)3 complex. This actinometer is quite sensitive to visible light and covers a broad wavelength range. However, the quantum yield does show a wavelength dependence (27), which also varies with the temperature and the pH of the solution. Moreover, because the same thiocyanate release is also observed as a result of the thermal degradation processes (the rate constants depend on the pH of the solution), appropriate control... 

The nickel complex, Ni ( 5115)2, has been made by the action of the Grignard reagent on nickel (II) acetylacetonate (217) or from potassium cyclopentadienyl and the ammine [Ni(NHs)el (S N)2 in liquid ammonia (58). It forms dark emerald-green crystals which sublime at 80-90° and which, when heated in nitrogen, melt, with decomposition and the formation of a nickel mirror, at 173-174°. It is only slowly oxidized in air, and cold water neither attacks nor dissolves it it is, however, readily soluble in organic liquids. Oxidation of the compound yields an orange-yellow solution containing the ion [Ni( 5H5)2]+, which is stable for a short period in weakly acidic media, and which may be precipitated as the reineckate or tetraphenylborate. 

Although attempts made so far to prepare complexes of the type Mn (aromatic)2 or [Mn(aromatic) 2] + have been unsuccessful, it has been possible to isolate a bright yellow tetraphenylborate of the [Re(C6He)2] + ion (as fine needles) and a red-brown reineckate of the [Re(sj/TO-(CHs)3 CeHs) 2] ion by the aluminum chloride method. The free bases are stable, but attempts at reduction to the uncharged complex of the element were unsuccessful (5S). 

Cyano- and thiocyanato-complexes of chromium are also common. Among the more interesting of these is Reinecke s salt, NH4[Cr(NH3)2(SCN)4]H20, made by adding (NH4)2Cr207 slowly to melted NH4SCN, washing with, and recrystallising from, alcohol. The octahedral ion has the form shown in Fig. 246. 

Reinecke H and Dunemann L (1990) Does the supplementation of metal ions modify the intrinsic distribution of element species in food extracts Eresenius J Anal Chem 338 630-634. 

Ferricinium perchlorate, nitrate, and chloride are readily soluble in water and alcohols, somewhat soluble in hydrocarbons, but insoluble in ether-type solvents. The ferricinium ion is blue, and it may be precipitated from solution as the triiodide, tungstosilicate, picrate, reineckate, etc. Ferricinium salts may be reduced to ferrocene by tin(II) chloride. 

Whereas Reinecke s salt is hardly used any more, Parker s solution has become the classical actinometer for photochemists. Iron(III) ions which are produced by irradiation have to be chelated by 1,10-phenanthroline in an acetate buffer after the photoreaction. The coloured complex must be photometrically determined at a wavelength of 510 nm after a complete conversion has taken place. The time delay has to be at least 1 h, overnight is preferable. The actinometric solution is restricted to wavelength areas below 450 nm. Some skill of the experimenter is required otherwise the errors amount to more than 10% [123,124]. 

Solvolysis of rm 5 -[Cr(NH3)2(NCS)4] ion (Reinecke s salt) has been studied recently in methanolic and ethanolic perchloric acid. Loss of thiocyanate from rra/i5 -[Cr(NCS)4(benzylamine)2]" ion in aqueous acetone, and ( C]thio-cyanate exchange with rm 5-[Cr(NH3)2(NCS)4)" ion have also been reported. 

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