Acids Ferric chloride-Silica

J-Butyl Ether. -Butyl ether is prepared by dehydration of -butyl alcohol by sulfuric acid or by catalytic dehydration over ferric chloride, copper sulfate, silica, or alumina at high temperatures. It is an important solvent for Grignard reagents and other reactions that require an anhydrous, inert medium. /7-Butyl ether is also an excellent extracting agent for use with aqueous systems owing to its very low water-solubility. 

Boduszynski et al. (1980) described an elaborate new separation procedure for isolating and concentrating chemically defined compound types rather than solubility types. A residuum (675°C+) is first fractionated by chromatography with an ion and cation resin to isolate acids and bases, followed by coordination chromatography on ferric chloride Attapulgas clay to separate the remaining neutral Lewis base and hydrocarbon fraction. This latter component is further separated into saturate and aromatic hydrocarbons over silica gel. 

Poly(w-carboranyl-siloxane) elastomers containing a mixture of di-methyl-and methyl(phenyl)-silyl units were synthesised using the Ferric Chloride catalyzed condensation reaction between di-chloro-di-organosilane and 1,7-bis(di-methyl(methoxy)silyl)-/w-carborane. Silica Nano tubes synthesised using i 7situ growth of DL Tartaric acid nanocrystals and concurrent sol-gel hydrolysis and condensation of silane. 

Separation Procedure. The petroleum asphaltenes were separated into five fractions acids, bases, neutral nitrogen compounds, saturate hydrocarbons, and aromatic hydrocarbons. Acids were isolated using anion-exchange resin, bases with cation-exchange resin, and neutral nitrogen compounds by complexation with ferric chloride adsorbed on Attapulgus clay. The remaining hydrocarbon fraction is separated on silica gel to produce saturate and aromatic hydrocarbon fractions. 

The common method for preparing a colloidal solution of hydrous ferric oxide, for example, has been to hydrolyze ferric chloride in solution by heat, and remove the hydrochloric acid by dialysis. Colloidal silica can be made in a similar way, that is, by dialyzing a solution of sodium silicate. One hydrolysis product—hydrochloric acid or sodium hydroxide—can pass through the membrane used for dialysis, whereas the colloidal particles of hydrous oxide cannot. The process is rather tedious and takes hours or even days. A much simpler method is to take out the acid or alkali with one of the solid ion exchangers or acid absorbers used in water purification. ... 

Balasubramanian et al. [42] accomplished microwave-assisted glycosylations in solution by irradiation of a mixture of 49a and tri-O-acetyl-o-galactal 49b with an appropriate alcohol or substituted phenol in the presence of montmorillonite K-10 as catalyst they obtained solely the corresponding a-anomers of unsaturated glycosides 50 and 51 in much shorter times and with better yields than those obtained by conventional heating (Scheme 12.25). Silica gel and ferric chloride were also used as catalysts, but either no reaction occurred or extensive decomposition occurred when these acids were used. 

This phenomenon could conceivably be developed into a method of following the decrease in available SiOH groups (or the surface area) as polymerization occurs. Hazel, Schock, and Gordon found that by titrating freshly made ferric chloride solu tion from time to time with a sol of silicic acid as the latter polymerizes, the amount of silica required to combine with a given amount of ferric ion increased with sol age. 

Resorcinol and its mono- and diacetates can be separated from one another and from hexachlorophene by TLC after extraction from dermatological preparations silica gel layers were used, prepared with 0.01 M aqueous sodium tungstate as complexing agent, benzene-dioxan-acetic acid (90 +10 + 2) as solvent and ferricyanide-ferric chloride (Rgt. No. Ill) for detection [64]. Hexyhesorcinol and hexachlorophene can be separated on silica gel G layers, using methyl isobutyl ketone [64]. A separation of dichlorophene and hexachlorophene has been possible with n-heptane,saturated with acetic acid,and layers of a hand prepared mixture of silica gel and starch binder [26]. Some of the components of tar oils and their TLC are also of pharmaceutical interest [130]. TLC-data for dithranol have also been described [15]. lodo-chlorhydroxyquin(5-chloro-8-hydroxy-7-iodoquinoline) has been separated from possible contaminants originating from its synthesis, by TLC in methanol on polyamide-calcium sulphate layers (5g polyamide + 3.5 g calcium srdphate + 10 ml water) [90]. 

Phenolic acids. Table 11 lists the Rf values for a number of phenolic acids and certain of their relatives on silica gel, silanized silica gel, cellulose, and polyamide layers. Silica gel (Silica Rapid Platten Woelm F-254) was used with solvents I [dichloromethane-toluene-formic acid (50 40 10)] and II [dichloromethane-acetic acid-water (100 50 50, lower phase)], followed by UV examination of the plates and subsequent spraying with 1 % methanolic ferric chloride. HPTLC precoated plates with silica gel 60 F-254, RP-8, and Wang polyamide were used with solvents 111 [benzene-ethyl acetate-formic acid (40 10 5)], IV [ethanol-water (55 45)], and IX [benzene-ethyl methyl ketone-methanol (60 26 14)], respectively. The upper part of Table 11 lists the Revalues of hydroxybenzoic acids and the lower part those for hydroxycinnamic acids. For columns V, VI, VII, and VIII, the solvents used were 2% formic acid (V), 20% potassium chloride solution (VI), isopropanol- ammonium hydroxide-water (8 1 1) (VII), and 10% acetic acid (VIII). For each layer the relative trends of the Revalues follow the polarity of the compounds listed. Table 12 gives the Revalues for certain phenolic acids on silver oxide-impregnated silica gel G by two-dimensional development on cellulose (107). 

Stationary phase silica gel G. Mobile phase M = acetone M2 = ethyl methyl ketone A/j = propan-2-ol M = 10% diphenylamine in methanol A/5 = 10% diethylamine hydrochloride (DEAH) in methanol A/ = formic acid (FA)-10% DEAH in methanol (9 1) A/7 = FA-acetone (1 9) Mi = FA-propan-2-ol (1 9) Mg = FA-propan-2-ol (9 1). Conditions Ascending technique, run 10 cm. layer thickness 0.25 mm. 1% test solutions as sodium or potassium salts of anions, activation temperature 100 S°C for I h, loading volume 10 )i.l. Detection (a) 1% ferric chloride solution in 2.0 M HCI for SCN , MoOl", FelCNjs" and Fe(CN). (b) Saturated solution of silver nitrate in methanol forCrOi", CraO ", S . ", VOj, Cl , T, Br , lOj, lOj and CHsCOO". (c) 1% solution of K1 in 1% HCI for NO2 and BrOj. Remarks Separation of microgram amounts of iodate from large excess of iodide, bromide, or chloride, and vice versa on silica gel layer with A/g. 

Patented proposals have been made to heat sodium chloride with phosphoric acid (A. Delhaye) zinc or lead pyrophosphate (L. J. F. Margueritte) or ferric phosphate (A. R. Arrott). The resulting soluble sodium phosphate is decomposed by boiling with lime to form sodium hydroxide, which, if needed, can be converted into carbonate by a current of carbon dioxide. These methods are quite impracticable. In 1809, J. L. Gay Lussac and L. J. Thenard proposed to make soda by the action of steam on a mixture of sodium chloride and silica If these two compounds are melted together there is very little action, for the salt volatilizes before anything but a superficial combination takes place, and the action of salt in the glazing of pottery is probably made possible by the aq. vapour in the furnace gases. The sodium silicate formed by the joint action of sodium and... 

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