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Carboxylic acid derivatives, functional groups

Dansyl chloride (DNS-Cl 5-dimethylaminonaphtha-lene-l-sulfonyl chloride) is used in analytical chemistry to fluorescently label substances. This process of dansyla-tion creates fluorescent derivatives, which can be detected with great sensitivity. The method for the dansylation of hydroxyl (-OH) and carboxylic acid (-COOH) functional groups has been described. Fluorescent labeling by dansyl chloride has applications in LC, HPLC, TLC, and MS. Fast TLC was accomplished using acetone as the resolving solvent, and resulted in good differentiation of analytes. [Pg.1656]

Because of the special importance of anhydrides of phosphoric acid in biological chemisfry we include them here to show their similarity with the anhydrides of carboxylic acids. The functional group of a phosphoric anhydride is two phosphoryl groups bonded to an oxygen atom. Here are structural formulas for two anhydrides of phosphoric add and the ions derived by ionization of each acidic hydrogen. [Pg.738]

This chapter differs from preceding ones in that it deals with several related classes of compounds rather than just one Although the compounds may encompass sev eral functional group types they share the common feature of yielding carboxylic acids on hydrolysis and for this reason are called carboxylic acid derivatives... [Pg.830]

Infrared IR spectroscopy is quite useful in identifying carboxylic acid derivatives The, carbonyl stretching vibration is very strong and its position is sensitive to the nature of IKT the carbonyl group In general electron donation from the substituent decreases the double bond character of the bond between carbon and oxygen and decreases the stretch mg frequency Two distinct absorptions are observed for the symmetric and antisym metric stretching vibrations of the anhydride function... [Pg.872]

In general, a hydroxamic acid function results from the condensation of a hydroxylamine group with a carboxylic acid derivative. If these two groups are positioned suitably in the same molecule, spontaneous cyclization can occur. The most usual technique involves... [Pg.210]

The most senior of other functional groups expressed in the suffix receives the lowest possible locant, i.e. carboxylic acid (derivatives) > (potential) ketonic carbonyl groups. [Pg.55]

A two-step procedure was required for the preparation of a diverse set of pyrrole-3-carboxylic acid derivatives. The diketone 15 was prepared using a functional homologation of a 6-ketoester 14 with different aldehydes followed by oxidation with PCC. The Paal-Knorr reaction was carried out in AcOH in a sealed tube under microwave irradiation (180 °C, 5-10 min) to give differently substituted pyrroles with a COOMe group in position 3 (Scheme 5). This group was further transformed to expand the diversity of the products prepared with this method [32]. [Pg.218]

Although the aminolysis of esters to amides is auseful synthetic operation, usually it presents some disadvantages in terms of drastic reaction conditions, long reaction times or strong alkali metal as catalyst, which are usually not compatible with other functional groups in the molecule [6]. For this reason, enzymatic aminolysis of carboxylic acid derivatives offers a clean and ecological way for the preparation of different kind of amines and amides in a regio-, chemo-, and enantioselective manner. [Pg.171]

When a multistep synthesis is being undertaken with other sensitive functional groups present in the molecule, milder reagents and reaction conditions may be necessary. As a result, many alternative methods for effecting interconversion of the carboxylic acid derivatives have been developed and some of the most useful reactions are considered... [Pg.243]

Such carbonyls may be further oxidized using potassium permanganate (KMnO and perchloric acid (HCIO4) to convert all of these groups into carboxylic acids. Once functionalized in this manner, the nanotubes can be fully dispersed in aqueous systems. Kordas et al. (2006) used these derivatives to print nanotube patterns on paper or polymer surfaces to create conductive patterns for potential use in electronic circuitry. The carboxylates also may be used as conjugation sites to link other ligands or proteins to the nanotube surface using a carbodiimide reaction as previously discussed (Section 1, this chapter Chapter 2, Section 1.11 Chapter 3, Section 1). [Pg.640]

In the particular case in which the carbonyl group belongs to a carboxylic acid derivative, such as an ester (17) or an amide (18) (or other functional groups which may be converted into it by a FGI), then they may be disconnected according to the "orthoacetate-modification" of the retro-Claisen rearrangement (Schemes 7.7 and 7.8) developed mainly by Eschenmoser [7] and Ziegler [8], independently, in the synthesis of alkaloids, and Johnson in a very simple and yet highly stereoselective synthesis of squalene [9]. [Pg.186]

A second route (route B in Fig. 1) relies on an initiation process with an (meth)acryl hydroxyl compound and is adopted from the chemical ROP of lactones. The controlled character of these polymerizations ensures a virtually quantitative initiation and thus incorporation of hydroxy-functional initiator (e.g., acrylate) into the polymer chain. However, this is not automatically the case for lipase-catalyzed ROP due to the different mechanism. The latter follows an activated monomer mechanism in which the lipase activates any carbonyl group of a carboxylic acid derivative present in the system. It has recently been shown that acrylation using hydroxy-functional acrylate initiators like hydroxy ethyl(meth)acrylate (HEMA or... [Pg.82]

Carboxylic acid derivatives (or acyl derivatives), RC—G, have the OH replaced by another electronegative functional group, G. such that it can be hydrolyzed back to the acid ... [Pg.345]


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Acidic function

Acidic functional groups

Acidic functionalities

Acidity functions

Acids carboxyl group

Carboxyl functional group

Carboxyl functionality

Carboxyl groups acidity

Carboxylate functionality

Carboxylic acid derivates

Carboxylic acid derivs

Carboxylic acid functional group

Carboxylic acid groups

Carboxylic acids, functional derivatives

Carboxylic functional groups

Carboxylic functionalities

Carboxylic functionalized

Carboxylic functions

Carboxylic-functionalization

Derivative function

Derived group

Function derived

Functional Group Derivatives

Functional carboxylic acid

Functionalized carboxylate

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