Exchange reaction, carboxylic

The a -brotnoacyl bromide 5 converts unreacted carboxylic acid 1 by an exchange reaction into the more reactive acyl bromide 3, which subsequently becomes a-brominated as formulated above ... 

Conversion of the carboxylic acid to the diethyl amide interestingly leads to an agent that exhibits the properties of a respiratory stimulant. One synthesis of this agent starts with the preparation of the mixed anhydride of nicotinic and benzene-sulfonic acid (4). An exchange reaction between the anhydride and diethyl benzenesulfonamide affords nikethemide (5). ... 

Chromium, (ri6-benzene)tricarbonyl-stereochemistry nomenclature, 1,131 Chromium complexes, 3,699-948 acetylacetone complex formation, 2,386 exchange reactions, 2,380 amidines, 2,276 bridging ligands, 2,198 chelating ligands, 2,203 anionic oxo halides, 3,944 applications, 6,1014 azo dyes, 6,41 biological effects, 3,947 carbamic acid, 2,450 paddlewheel structure, 2, 451 carboxylic acids, 2,438 trinuclear, 2, 441 carcinogenicity, 3, 947 corroles, 2, 874 crystal structures, 3, 702 cyanides, 3, 703 1,4-diaza-1,3-butadiene, 2,209 1,3-diketones... 

These compounds are the most stable of the three classes of organothal-lium(III) derivatives and have been prepared by a wide variety of classical organometallic procedures. Many exchange reactions of TIX3 (X = Cl, carboxylate) with organo derivatives of boron, mercury, tin, lead, etc., have been shown to result in formation of R2TIX compounds 73, 78), but are of relatively little preparative significance. The most frequently used procedure... 

The unsaturated retro-Michael product easily isomerizes to a dicarbonyl when the Cy also carries a hydroxyl group (X = OH in Fig. 2.3). Such components are notoriously unstable. They undergo decarbonylation to a shorter aldehyde and CO. The retro-Michael product can also be converted into a carboxylic acid via hydration of the aldehyde function (Fig. 2.3). Notably, the formation of the carboxylic acid is accompanied by the saturation of the Cp it in fact represents an exchange reaction between the OH, and the aldehydic H. 

A second interfacial exchange reaction of the o-acylcobalt complex with hydroxide ion leads to the production of the alkanecarboxylate anion, which migrates into the aqueous phase, leaving the cobalt tetracarbonyl anion in the organic phase for subsequent reaction (Scheme 8.2). Optimum yields of the carboxylic acids are obtained with ca. 40 1 ratio of the alkyl halide to dicobalt octacarbonyl. Co(Ph,P)2Cl2 can also be used and has the advantage that the cobalt can be recycled easily [5]. 

Calculated for equimolar exchange with carboxyl groups (NaHCOg and NajCOj neutralization) and equivalent reaction with phenol groups. 

The water-soluble OX-Dex/CDDP and DCM-Dex/CDDP conjugates were easily obtained by the ligand-exchange reaction of hydroxo-CDDP with the corresponding dextran derivatize with carboxylic acid groups. 

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