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Potassium hydroxide sulphate

Why is potassium aluminium sulphate not soluble in benzene A compound M has the composition C = 50.0% H=12.5%o A1 = 37.5%. 0.360 g of M reacts with an excess of water to evolve 0.336 1 of gas N and leave a white gelatinous precipitate R. R dissolves in aqueous sodium hydroxide and in hydrochloric acid. 20 cm of N require 40 cm of oxygen for complete combustion, carbon dioxide and water being the only products. Identify compounds N and R, suggest a structural formula for M, and write an equation for the reaction of M with water. (All gas volumes were measured at s.t.p.)... [Pg.159]

Boil 2 g. of the ester with 30 ml. of 10 per cent, sodium or potassium hydroxide solution under reflux for at least 1 hour. If the alcohol formed is water (or alkali) soluble, the completion of the hydrolysis will be indicated by the disappearance of the ester layer. Distil ofiF the liquid through the same condenser and collect the first 3-5 ml. of distillate. If a distinct la3 er separates on standing (or upon saturation of half the distillate with potassium carbonate), remove this layer with a capillary dropper, dry it with a little anhydrous potassium carbonate or anhydrous calcium sulphate, and determine the b.p. by the SiwoloboflF method... [Pg.391]

In a 250 ml. distilling flask (1) place 122 g. (119 ml.) of p-phenylethyl alcohol and 40 g. of sodium hydroxide peUets (or 56 g. of potassium hydroxide). Heat is evolved. Warm gently until bubbles commence to form and the mixture separates into two sharply-defined layers. Distil slowly water, etc. passes over first accompamed by the gradual dis appearance of the upper phase. FinaUy the styrene passes over at 140 160° (mainly 150°) coUect this separately in a receiver containing about 0 1 g. of hydroquinone. Dry the distillate with a httle anhydrous calcium chloride or magnesium sulphate, and then distil under reduced pressure (2). C oUect the pure styrene at 42-43°/18 mm. The 3rield is 80 g. Add about 0-2 g. of hydroquinone (anti-oxidant) if it is desired to keep the phenylethylene. [Pg.1024]

Seheuing and Winterhalder treated 2 6-distr3rrylpyridine tetra-bromide with potassium hydroxide in alcohol, so producing 2 6-di-)3-phenylacetylenylpyridine (XI) which by the action of 50 per cent, sulphuric acid was converted into 2 6-diphenacylpyridine (XII), and this, on hydrogenation in presence of platinic oxide, barium sulphate and methyl alcohol, was reduced to 2 6-di-(6-hydroxy-(6-phenylethylpyridine, and the hydrochloride of this, on similar catalytic hydrogenation, yielded worlobelanidine (XIII). This can be methylated to lobelanidine, from which in turn dMobeline and lobelanine can be obtained. [Pg.25]

This with potassium hydroxide in methanol forms de-OiV-dimethylarmepavine, m.p. 86-7°, (B. HCl, m.p. 229-30°) of which the methiodide, m.p. 233-4°, on treatment with alkali decomposes into trimetHylamine and a -p-anisyl-/3-(3 4-dimethoxy- 6 - vinylphenyl) -ethylene, m.p. 79°. The latter is oxidised by permanganate in acetone to anisic and m-hemipinic acids. With ethyl sulphate and alkali, armepavine gives 0-ethylarmepavine, an oil, which permanganate oxidises to p-ethoxybenzoic acid. Armepavine is similarly oxidised to p-hydroxybenzoic acid and l-keto-6 7-dimethoxy-2-methyl-1 2 3 4-tetiahydrowoquinoline and is therefore 6 7-dimethoxy-l-p-hydroxybenzyI-2-methyI-l 2 3 4-tetrahydrowoquinoline, i.e., it is laudanosine (p. 187) with MeO. at C replaced by H and MeO at C changed to HO. ... [Pg.196]

The ethyl ether of hydroquinone, para oxyphenetol, CgHj(,02, is found to a small extent in oil of star aniseed. It can also be prepared artificially by heating para-diazophenetol sulphate with dilute sulphuric acid, or by boiling hydroquinone with ethyl iodide and potassium hydroxide under a reflux condenser. Its constitution is—... [Pg.259]

As follows from the results obtained, numerous parameters influence the quality of precipitates, vs raw materials used (such as, manganese sulphate, nitrate, chloride) pH of initial and final solutions the excess of the oxidant the type of a neutralizing agent (lithium, sodium, potassium hydroxide) the washing method, and pH of leachates. More detailed description of the synthetic routine will be published elsewhere. [Pg.483]

Anhydrous sodium sulphate, even when freshly ignited before use, is much less active than calcium chloride. It is used when a substitute for calcium chloride is indicated for the reasons given above. For solutions of basic substances ignited potassium carbonate, solid potassium hydroxide, and barium oxide are much used as drying agents. [Pg.34]

In contrast, liquidiliquid phase-transfer catalysis is virtually ineffective for the conversion of a-bromoacetamides into aziridones (a-lactams). Maximum yields of only 17-23% have been reported [31, 32], using tetra-n-butylammonium hydrogen sulphate or benzyltriethylammonium bromide over a reaction time of 4-6 days. It is significant that a solidiliquid two-phase system, using solid potassium hydroxide in the presence of 18-crown-6 produces the aziridones in 50-94% yield [33], but there are no reports of the corresponding quaternary ammonium ion catalysed reaction. Under the liquidiliquid two-phase conditions, the major product of the reaction is the piperazine-2,5-dione, resulting from dimerization of the bromoacetamide [34, 38]. However, only moderate yields are isolated and a polymer-supported catalyst appears to provide the best results [34, 38], Significant side reactions result from nucleophilic displacement by the aqueous base to produce hydroxyamides and ethers. [Pg.183]


See other pages where Potassium hydroxide sulphate is mentioned: [Pg.330]    [Pg.228]    [Pg.43]    [Pg.142]    [Pg.257]    [Pg.469]    [Pg.488]    [Pg.517]    [Pg.769]    [Pg.804]    [Pg.812]    [Pg.856]    [Pg.880]    [Pg.917]    [Pg.935]    [Pg.955]    [Pg.975]    [Pg.229]    [Pg.586]    [Pg.729]    [Pg.272]    [Pg.53]    [Pg.142]    [Pg.257]    [Pg.469]    [Pg.488]    [Pg.769]    [Pg.804]    [Pg.812]    [Pg.856]    [Pg.880]    [Pg.917]    [Pg.935]    [Pg.955]    [Pg.975]    [Pg.267]    [Pg.255]    [Pg.196]    [Pg.128]   
See also in sourсe #XX -- [ Pg.687 , Pg.688 ]




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