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Alkaline derivatives

As already mentioned, when simple alkaline derivatives, such as sodium alcoho-lates, soda or potash, are used as catalysts, one arrives at a pure product usable as fuel and a glycerol at the required standard only after many stages. [Pg.329]

Sulfur Compounds Present in Refining Solutions. Acid and alkaline derivatives are discussed separately. [Pg.401]

Norgren, M., Edlund, H., Wagberg, L. Aggregation of lignin derivatives under alkaline derivatives. Kinetic and aggregate structure. Langmuir 18, 2856-2865 (2002)... [Pg.310]

The description of basic substances as alkaline derives from the Arabie word al-qali, meaning plant ashes." Potassium carbonate, commonly known as potash, is found in ashes from wood fires. Long ago it was discovered that this compound dissolves in water to yield a solution that feels slippery, tastes bitter, and reacts with acids. [Pg.189]

Summary Alkaline derivatives of silanols and aminosilanols are isolated as rings, cubanes and prisms. They react stepwise with element halides to give chains or four-, six-, and eight-membered SiO and SiOSiN ring molecules. In these reactions, for example, the smallest four-membered rings containing two silicon atoms and the longest Si-0 chains were formed. Syntheses and structures are presented. [Pg.254]

The alkaline derivatives of silanols and aminosilanols shown in Fig. 1 have been the starting materials for preparation of SiO and SiOSiN chains, rings and cages. [Pg.254]

In contrast to carbon chemistry, in silicon chemistry diols and silanol halides can be stabilized by bulky groups. Stepwise synthesis of cyclic and acyclic siloxanes is possible with fluorosilanes and alkaline derivatives (Scheme 1). [Pg.254]

Hammen equation A correlation between the structure and reactivity in the side chain derivatives of aromatic compounds. Its derivation follows from many comparisons between rate constants for various reactions and the equilibrium constants for other reactions, or other functions of molecules which can be measured (e g. the i.r. carbonyl group stretching frequency). For example the dissociation constants of a series of para substituted (O2N —, MeO —, Cl —, etc.) benzoic acids correlate with the rate constant k for the alkaline hydrolysis of para substituted benzyl chlorides. If log Kq is plotted against log k, the data fall on a straight line. Similar results are obtained for meta substituted derivatives but not for orthosubstituted derivatives. [Pg.199]

These compounds are obtained by action of halogenated organic derivatives on lead alloys (magnesium or alkaline metal alloys). [Pg.352]

Colorations or coloured precipitates are frequently given by the reaction of ferric chloride solution with.(i) solutions of neutral salts of acids, (ii) phenols and many of their derivatives, (iii) a few amines. If a free acid is under investigation it must first be neutralised as follows Place about 01 g. of the acid in a boiling-tube and add a slight excess of ammonia solution, i,e., until the solution is just alkaline to litmus-paper. Add a piece of unglazed porcelain and boil until the odour of ammonia is completely removed, and then cool. To the solution so obtained add a few drops of the "neutralised ferric chloride solution. Perform this test with the following acids and note the result ... [Pg.332]

Amides (except urea and thiourea), imides and nitriles, after the above alkaline hydrolysis, give derivatives similarly to those from the alkaline solution obtained from ammonium salts (p. 360). (A) If the original compound is aromatic, acidification of the cold solution deposits the crystalline acid. (B) The cold solution, when carefully neutralised (p. 332) and treated with benzylthiuronium chloride, deposits the thiuromum salt. [Pg.361]

It is frequently advisable in the routine examination of an ester, and before any derivatives are considered, to determine the saponification equivalent of the ester. In order to ensure that complete hydrolysis takes place in a comparatively short time, the quantitative saponi fication is conducted with a standardised alcoholic solution of caustic alkali—preferably potassium hydroxide since the potassium salts of organic acids are usuaUy more soluble than the sodium salts. A knowledge of the b.p. and the saponification equivalent of the unknown ester would provide the basis for a fairly accurate approximation of the size of the ester molecule. It must, however, be borne in mind that certain structures may effect the values of the equivalent thus aliphatic halo genated esters may consume alkali because of hydrolysis of part of the halogen during the determination, nitro esters may be reduced by the alkaline hydrolysis medium, etc. [Pg.392]

Crystalline derivatives of amino acids are usually produced by reaction at the amino group by treatment with appropriate reagents in alkaline solution ... [Pg.436]

Method 1. Treat 2 0 g. of the mixture of amines with 40 ml. of 10 per cent, sodium hydroxide solution and add 4 g. (3 ml.) of benzenesulphonyl chloi de (or 4 g. of p-toluenesulphonyl chloride) in small portions. Warm on a water bath to complete the reaction. Acidify the alkaline solution with dilute hydrochloric acid when the sulphonamides of the primary and secondary amines are precipitated. Filter off the solid and wash it with a little cold water the tertiary amine will be present in the filtrate. To convert any disulphOnamide that may have been formed from the primary amine into the sulphonamide, boil the solid under reflux with 2 0 g. of sodium dissolved in 40 ml. of absolute ethyl alcohol for 30 minutes. Dilute with a little water and distil off the alcohol filter off the precipitate of the sulphonamide of the secondary amine. Acidify the filtrate with dilute hydrochloric acid to precipitate the derivative of the primary amine. Recrystallise the respective derivatives from alcohol or from dilute alcohol, and identify them inter alia by a determination of the m.p. [Pg.651]

Suspend 1 g. (or 1 ml.) of the substance in 20 ml. of 5 per cent, sodium hydroxide solution in a well-corked boiling tube or small conical flask, and add 2 ml. of redistilled benzoyl chloride, ca. 0-5 ml. at a time, with constant shaking, and cooling in water (if necessary). Shake vigorously for 5-10 minutes until the odour of the benzoyl chloride has disappeared. Make sure that the mixture has an alkaline reaction. Filter oflF the solid benzoyl derivative, wash it with a little cold water, and recrystalHse it from alcohol or dilute alcohol. [Pg.652]

If the presence of a disulphonyl derivative from a primary amine is suspected (e.., formation of a precipitate in alkaline solution even after dilution), reflux the precipitate, obtained after acidifyim , with a solution of I g. of sodium in 20 ml. of rectifled spirit for 15 minutes. Evaporate the alcohol, dilute with water, and filter if necessary acidify with dilute hydrochloric acid. Collect the sulphonyl derivative and recrystallise it from alcohol or dilute alcohol. [Pg.653]

Anthranilic acid. This substance, the ortho amino derivative of benzoic acid, may be conveniently prepared by the action of sodium hypobromite (or sodium hypochlorite) solution upon phthalimide in alkaline solution at 80°. The ring in phthalimide is opened by hydrolysis to phthalamidic acid and the latter undergoes the Hofmann reaction (compare Section 111,116) ... [Pg.754]

Another method for the hydroxylation of the etliylenic linkage consists in treatment of the alkene with osmium tetroxide in an inert solvent (ether or dioxan) at room temperature for several days an osmic ester is formed which either precipitates from the reaction mixture or may be isolated by evaporation of the solvent. Hydrolysis of the osmic ester in a reducing medium (in the presence of alkaline formaldehyde or of aqueous-alcoholic sodium sulphite) gives the 1 2-glycol and osmium. The glycol has the cis structure it is probably derived from the cyclic osmic ester ... [Pg.894]

In a 1 htre round-bottomed flask, provided with an air condenser, place a mixture of 25 g. (26 ml.) of pure dimethylanihne, 10 g. of Michler s ketone (4 4 tetramethyldiaminobenzophenone) and 10 g. (6 ml.) of phosphorus oxychloride. Heat on a boding water bath for 5 hours. Add about 150 ml. of water and sufificient sodium hydroxide solution to render the solution alkaline. Calculate the quantity of sodium hydroxide required upon the basis of the hydrolysis product derived from the phosphorus oxychloride ... [Pg.982]

The reactivity of the amino radical has not yet been investigated. Alkaline hypochlorite oxidation, known in the pyridine series to yield azo derivatives (155,156). and photolysis of N,N-dichloro derivatives, which may be obtained by action of sodium hypochlorite on amino derivatives in acidic medium (157). should provide interesting insight on this reactivitv. [Pg.31]


See other pages where Alkaline derivatives is mentioned: [Pg.38]    [Pg.3]    [Pg.30]    [Pg.1679]    [Pg.449]    [Pg.280]    [Pg.160]    [Pg.38]    [Pg.28]    [Pg.177]    [Pg.111]    [Pg.38]    [Pg.3]    [Pg.30]    [Pg.1679]    [Pg.449]    [Pg.280]    [Pg.160]    [Pg.38]    [Pg.28]    [Pg.177]    [Pg.111]    [Pg.19]    [Pg.72]    [Pg.120]    [Pg.208]    [Pg.257]    [Pg.340]    [Pg.376]    [Pg.416]    [Pg.2777]    [Pg.395]    [Pg.650]    [Pg.786]    [Pg.786]    [Pg.1071]    [Pg.1073]    [Pg.1075]    [Pg.163]    [Pg.165]    [Pg.115]   
See also in sourсe #XX -- [ Pg.329 ]




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