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Salt substitute, sodium primary

Dissolve 0 5 g. of the primary amine and 0-5 g. of pure phthaUc anhydride in 5 ml. of glacial acetic acid and reflux for 20-30 minutes. (If the amine salt is used, add 1 g. of sodium acetate.) The N-substituted phthaUmide separates out on cooling. Recrystallise it from alcohol or from glacial acetic acid. [Pg.423]

With sodium azide, salts of secondary nitroparaffins rearrange to N-substituted amides (29). With SO2, primary or secondary nitroparaffins give imidodisulfonic acid salts (30). Potassium nitroform reacts quantitatively with nitryl chloride in ether to form tetranitromethane (31). [Pg.99]

Primary nitroparaffins react with two moles of formaldehyde and two moles of amines to yield 2-nitro-l,3-propanediamines. With excess formaldehyde, Mannich bases from primary nitroparaffins and primary amines can react further to give nitro-substituted cycHc derivatives, such as tetrahydro-l,3-oxa2iaes or hexahydropyrimidines (38,39). Pyrolysis of salts of Mannich bases, particularly of the boron trifluoride complex (40), yields nitro olefins by loss of the amine moiety. Closely related to the Mannich reaction is the formation of sodium 2-nitrobutane-1-sulfonate [76794-27-9] by warming 1-nitropropane with formaldehyde and sodium sulfite (41). [Pg.100]

Where X is Br or Q, the free acids may be obtained by acidification of the alkaline solution, but where X is I, the acids must be isolated as salts to avoid reduction of the arsonic acids by HI. Rather than using alkyl haUdes, alkyl or dialkyl sulfates or alkyl arenesulfonates can be used. Primary alkyl haUdes react rapidly and smoothly, secondary haUdes react only slowly, whereas tertiary haUdes do not give arsonic acids. AHyl haUdes undergo the Meyer reaction, but vinyl hahdes do not. Substituted alkyl haUdes can be used eg, ethylene chlorohydrin gives 2-hydroxyethylarsonic acid [65423-87-2], C2H2ASO4. Arsinic acids, R2AsO(OH), are also readily prepared by substituting an alkaU metal arsonite, RAs(OM)2, for sodium arsenite ... [Pg.337]

For ammonia and primary amines there are two possible pathways, but when secondary amines are involved, only the hydrogenolysis pathway is possible. Other reducing agents167 can be used instead of hydrogen and a catalyst, among them zinc and HCI, sodium cyano-borohydride NaBHjCN,168 sodium triacetoxyborohydride,169 sodium borohydride,170 iron pentacarbonyl and alcoholic KOH,171 BH -pyridine,172 and formic acid. When the last is used, the process is called the Wallach reaction. In the particular case where primary or secondary amines are reductively methylated with formaldehyde and formic acid, the method is called the Eschweiler-Clarke procedure. It is possible to use ammonium (or amine) salts of formic acid,173 or formamides, as a substitute for the Wallach conditions. This method is called the Leuckart reaction, and in this case the products obtained are often the N-formyl derivatives of the amines instead of the free amines. Primary and secondary amines can be N-ethylated (e.g., ArNHR —< ArNREt) by treatment with NaBH4 in acetic acid.175... [Pg.899]

The heart of the preparation of capsaicin is a malonic ester synthesis. The first step is bromination of the primary alcohol by phosphorous tribromide. The resulting primary alkyl bromide is used to alkylate the sodium salt of diethyl malonate. A substituted malonic acid derivative is obtained following basic hydrolysis of the ester groups. [Pg.594]

The use of sodium salt (II) is strongly recommended for nucleophilic amination of primary halides under anhydrous conditions. Both reagents (I) and (II) can be considered as useful substitutes of potassium phthalimide, free from well known preparative inconveniences involving application of the latter. [Pg.172]

Having reviewed the latest developments in synthetic chemistry, several other aspects of the radical-polar crossover reaction have been investigated. One of these concerns attempts to effect S, 2 substitutions at the hitherto unreactive primary tetrathiafulvalenium salts. Three potential nucleophiles have been examined, and whereas each has afforded a facile reaction, none effected a simple S 2 displacement. First, attack by sodium azide on a series of primary tetrathiafulvalenium salts led to formation of TTF, but not by direct displacement. The route shown in Scheme 10 for (3c) could explain the observed products although the thioketene (59) was never isolated in these reactions. [Pg.140]

Sodium salts of carboxylic acids, including hindered acids, such as mesitoic, rapidly react with primary and secondary bromides and iodides at room temperature in dipolar aprotic solvents, especially HMPA, to give high yields of carboxylic esters. The mechanism is Sn2. Several bases or basic media have been used to generate the carboxylate salt. Sodium salts are often used, but potassium, silver, cesium, and substituted ammonium salts have also been used. An important... [Pg.539]

Ammonium salts with two different alkyl chains were prepared directly via subsequent alkylations of dimethylamine with primary bromides and crystallization. Commercial hexadecyl-methylamine can be conveniently applied in the same way in order to convey functionality to cationic synkinons. A recent example describes subsequent alkylations with a small functional and a long-chain primary bromide (Scheme 2.4). A-acylated / -phenylenediamine was also alkylated at the second nitrogen atom which had two different alkyl chains, with or without extra functionality . After deacylation, this head group can be diazotized or coupled oxidatively with various heterocycles in water (Scheme 2.4). Photoactive and coloured membrane surfaces are thus obtained. Phenylene-diamine, pyridine and in particular A-methyl-4,4-bipyridinium chloride are relatively weak nucleophiles. Substitution of bromides is slow and the more reactive iodides can rarely be obtained commercially, but the selection of nitromethanes as solvent for bromide substitution is of great help as well as the addition of sodium iodide to enforce a Finkelstein reaction or a combination of both. [Pg.11]


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Salt primary

Salt substitute, sodium

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