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From carboxylate salts

Phenacyl esters, easily prepared from carboxylic salts and phenacyl bromide nnder phase transfer catalysis, regenerate the original carboxylic acid by treatment with sodinm hydrogen telluride in DMF. ... [Pg.157]

From carboxylate salts, thionyl chloride, and alcohols R OH + SOCI2—> R OSOCI -+- HO alkyi chlorosulfite RC02Na + R OSOCI —> RC02R + S02 H- NaCI Limited to primary alcohols it amounts to an Sn2 displacement of chlorosulfite group by carboxylate ion steric hindrance in the carboxylate salt seems unimportant. [Pg.856]

From carboxylate salts and alkyl halides RC02Na + R X — RC02R + NaX Restricted to primary halides with high Sn2 reactivity. [Pg.856]

Scheme 5.4. Synthesis of Ketones from Carboxylate Salts... Scheme 5.4. Synthesis of Ketones from Carboxylate Salts...
A special application of the Japp-Klingemann/Eischer sequence is in the preparation of tryptamines from piperidone-3-carboxylate salts, a method which was originally developed by Abramovitch and Shapiro[2]. When the piperidone is subjected to Japp-Klingemann coupling under mildly alkaline conditions decarboxylation occurs and a 3-hydrazonopiperidin-2-one is isolated. Fischer cyclization then gives 1-oxotetrahydro-p-carbolines which can be hydrolysed and decarboxylated to afford the desired tryptamine. [Pg.67]

Amides are sometimes prepared directly from carboxylic acids and amines by a two step process The first step is an acid-base reaction m which the acid and the amine combine to form an ammonium carboxylate salt On heating the ammonium carboxy late salt loses water to form an amide... [Pg.860]

Methyl group (Section 2 7) The group —CH3 Mevalonic acid (Section 26 10) An intermediate in the biosyn thesis of steroids from acetyl coenzyme A Micelle (Section 19 5) A sphencal aggregate of species such as carboxylate salts of fatty acids that contain a lipophilic end and a hydrophilic end Micelles containing 50-100 car boxylate salts of fatty acids are soaps Michael addition (Sections 18 13 and 21 9) The conjugate ad dition of a carbanion (usually an enolate) to an a 3 unsatu rated carbonyl compound... [Pg.1288]

Saponification (Section 20 11) Hydrolysis of esters in basic solution The products are an alcohol and a carboxylate salt The term means soap making and denves from the process whereby animal fats were converted to soap by heating with wood ashes... [Pg.1293]

Color intensity and permanence are improved by metal carboxylate salts, especially 2inc salts (83), which cataly2e the dye development and stabili2e the dye in its colored form. The substituted novolak resin, along with extender and binder, can be apphed to the receiving sheet as a solution or aqueous dispersion. Aqueous dispersions are probably the most widely used they are manufactured by the resin suppher or the user from the base resin. [Pg.304]

To place the acidity of phenol in perspective, note that although phenol is more than a million times more acidic than ethanol, it is over a hundred thousand times weaker than acetic acid. Thus, phenols can be separated from alcohols because they are more acidic, and from carboxylic acids because they are less acidic. On shaking an ether solution containing both an alcohol and a phenol with dilute sodium hydroxide, the phenol is converted quantitatively to its sodium salt, which is extracted into the aqueous phase. The alcohol remains in the ether phase. [Pg.997]

Reactant and product structures. Because the transition state stmcture is normally different from but intermediate to those of the initial and final states, it is evident that the stmctures of the reactants and products should be known. One should, however, be aware of a possible source of misinterpretation. Suppose the products generated in the reaction of kinetic interest undergo conversion, on a time scale fast relative to the experimental manipulations, to thermodynamically more stable substances then the observed products will not be the actual products of the reaction. In this case the products are said to be under thermodynamic control rather than kinetic control. A possible example has been given in the earlier description of the reaction of hydroxide ion with ester, when it seems likely that the products are the carboxylic acid and the alkoxide ion, which, however, are transformed in accordance with the relative acidities of carboxylic acids and alcohols into the isolated products of carboxylate salt and alcohol. [Pg.6]

Electrochemical reduction of oxazolinium salts 36 gives the anions 37, which add efficiently to alkyl halides or, in the presence of McsSiCl, to methyl acrylate, methyl vinyl ketone, and acrylonitrile. Simple acid hydrolysis then gives the ketone products 38 and 39, and this method is quite general since the starting salts are readily prepared from carboxylic acids, R C02H (87TL4411). [Pg.94]

The anodic oxidation of the carboxylate anion 1 of a carboxylate salt to yield an alkane 3 is known as the Kolbe electrolytic synthesis By decarboxylation alkyl radicals 2 are formed, which subsequently can dimerize to an alkane. The initial step is the transfer of an electron from the carboxylate anion 1 to the anode. The carboxyl radical species 4 thus formed decomposes by loss of carbon dioxide. The resulting alkyl radical 2 dimerizes to give the alkane 3 " ... [Pg.183]


See other pages where From carboxylate salts is mentioned: [Pg.148]    [Pg.148]    [Pg.59]    [Pg.997]    [Pg.516]    [Pg.442]    [Pg.381]    [Pg.174]    [Pg.498]    [Pg.788]    [Pg.459]    [Pg.156]    [Pg.488]   
See also in sourсe #XX -- [ Pg.1247 ]




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Aldehydes from carboxylic acid salts

Anhydrides from carboxylic acid salts

Carboxylate salts

Carboxylic Acids, isolation from salts

Carboxylic Acids, isolation from salts reactions

Carboxylic acids ammonium salts from

Carboxylic salts

Carboxylic salts, from

Carboxylic salts, from

Esters from carboxylate salts

Esters from carboxylic acid salts

From carboxylic acid salts

Hydrocarbons from carboxylate salts

Imine salts from carboxylic acids

Nitriles from carboxylate salts

Synthesis of ketones from carboxylate salts

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