Solvents antimony trichloride

The standard chemical and biological methods of analysis are those accepted by the JnitedStates Pharmacopeia XXIII as well as the ones accepted by the AO AC in 1995 (81—84). The USP method involves saponification of the sample (dry concentrate, premix, powder, capsule, tablet, or aqueous suspension) with aqueous alcohoHc KOH solvent extraction solvent removal chromatographic separation of vitamin D from extraneous ingredients and colormetric deterrnination with antimony trichloride and comparison with a solution of USP cholecalciferol reference standard. 

Antimony trichloride is used as a catalyst or as a component of catalysts to effect polymerisation of hydrocarbons and to chlorinate olefins. It is also used in hydrocracking of coal (qv) and heavy hydrocarbons (qv), as an analytic reagent for chloral, aromatic hydrocarbons, and vitamin A, and in the microscopic identification of dmgs. Liquid SbCl is used as a nonaqueous solvent. 

Antimony trichloride [10025-91-9] M 228.1, m 73", b 283", pK 1.4, pK j ll.O (11.8), PKI 12.95 (for Sb " " aquo). Dried over P2O5 or by mixing with toluene or xylene and distilling (water is carried off with the organic solvent), then distd twice under dry nitrogen at 50mm, degassed and sublimed twice in a vacuum into ampoules. Can be crystd from CS2. Deliquescent. Fumes in moist air. 

The benzobisazole family of rigid-rod polymers is soluble in acidic solvents such as PPA, methanesulfonic acid, chlorosulfonic acid, 100% sulfuric acid and Lewis acid salts such as antimony trichloride and bismuth trichloride. More recently, PBZT has been reported [22] to form liquid crystalline solutions in nitromethane containing aluminum trichloride or gallium trichloride. Since the glass transition temperature of these materials is above their decomposition temperature, they must be processed from solution. 

The 5,6,7-cis-triene configuration of vitamin D3 is important for its biological activity as the 5,6-trans form has very low activity. Exposure to iodine in non-polar solvents under diffuse light (39,40) or to mild acidic conditions (41) affords formation of the 5,6-trans isomer. The reverse transformation occurs photochemically (42). The 5,6-trans isomer can undergo further isomerizations upon exposure to heat (43) or acids or treatment with antimony trichloride. The cis and the trans forms of vitamin D3 display characteristic ultraviolet properties. The cis form as shown earlier has a UV maxima at 265 nm. The trans form has a UV maxima at 273 nm. 

At the starting point of the chromatogram, apply 0.015 mL of the Standard Solution and 0.01 mL of the Sample Solution. Develop the chromatogram in the chromatographic chamber lined with filter paper dipping into the solvent mixture. When the solvent has ascended 10 cm, remove the plate, allow it to dry in air, and spray it with antimony trichloride TS. The blue spot formed is indicative of the presence of retinol. The approximate Rf values of the predominant spots, corresponding to the different forms of retinol, are 0.1 for the alcohol, 0.45 for the acetate, and 0.7 for the palmitate. 

Adenine will dissolve in compounds such as antimony trichloride and IR and Raman spectral data in this solvent are also consistent with the primary amino structure as are data on polycrystalline adenine (74JCP(71)415). Similarly, IR spectra of guanine in the solid state support the oxoamino structure, and related work with thioxopurines shows a strong band at 1323 cm and absence of bands at 2500 cm in the solid state which favor the thioxo structures (55JA2569). 

The related reaction with alkyl nitrites generates purinyl radicals, which will efficiently abstract halogen from halogenated solvents, and this procedure is generally to be preferred for the transformation of an amino-purine into a halo-purine. ° These reactions can be improved/enhanced by the addition of antimony trichloride. Comparably, the use of dimethyl disulfide produces methylthio-purines, and trimethylsilyl azide, azido-purines. "... 

More suitable for, especially, the triarylstibines of higher molecular weight, is the reaction of aryl halides, antimony trichloride, and an excess of sodium in benzene or xylene, as discovered by Michaelis and Reese 513 ether cannot be used as solvent as the necessary reaction temperature cannot then be attained.514... 

Unfortunately it is impossible to estimate these shifts theoretically in any convincing manner, and of course truly reliable interpretations can only be obtained by direct comparison with known spectra of suitable reference compounds containing charged carbon atoms. At the present time infrared spectra of known aliphatic carbonium ions are not available in the literature however, the recent investigations of Baughan and co-workers (141, 142) provided a direct route for obtaining such data. They demonstrated, by cryoscopic and conductivity studies, that stable solutions of aliphatic carbonium ions could be obtained in fused antimony trichloride via ionization of aliphatic chlorides. Conveniently, this solvent is an excellent medium for infrared spectroscopy. In a preliminary study (103) the infrared spectra of the butenyl... 

Some aromatic hydrocarbons (e.g. perylene) give cation radicals in (neat) antimony trichloride solutions at 75° (Porter et al., 1970 Johnson, 1971). However, the cation radicals are not formed in the absence of oxygen. In fact, molten antimony trichloride can be used as a solvent at 99° for the anodic oxidation of perylene, naphthacene, and other polynuclear aromatics, provided that the electrolyte (e.g. KC1) is highly dissociated (Bauer et al., 1971). When a more covalent electrolyte (e.g. A1C13) is used, the solvent system itself becomes the oxidant [(17) and (18)]. 

As was previously mentioned, Artephius described the process of the Philosophers Stone using Antimony in about 1120 or 1150 CE. It rapidly became the divine Wet Method of producing the Philosophers Stone used by all the great alchemists. Antimony Trichloride is today widely used as an excellent non-aqueous solvent, especially for chloride-ion transfer-reactions. It avoids troublesome nitrates altogether by using chloride ion transfer. 

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