Acids with Other Functional Groups

T0281 Environmental Resources Management Corporation (ERM), Advanced Fluidized Composting (AFC) 

T0297 EPOC Water, Inc., Microtiltration Technology (EXXFLOW and EXXPRESS) T0355 Granular Activated Carbon (GAC)—General 

T0367 Harding ESE, Inc., In Situ Vadose Zone Soil Treatment T0371 High Voltage Environmental Applications, Inc., High-Energy Electron Beam Irradiation 

T0406 In Situ Soil Vapor Extraction (SVE)—General 

T0473 Lawrence Livermore National Laboratory, Direct Chemical Oxidation 

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Amino Acids with Other Functional Groups as Part of the Side Chain 38... 

Acrylic Acid Propenoic Acid Benzoic Acid Carboxylic Acids Carboxylic Acids and Derivatives Carboxylic Acids with Other Functional Groups Carboxylic Acids with Other Functional Groups Dichlorophenoxyacetic Acid 2,4-d Cesium... 

CARBOXYLIC ACIDS WITH OTHER FUNCTIONAL GROUPS... 

Carboxylic Acids with Other Functional Groups... 

Dichlorophenoxyacetic add 2,4-D under Carboxylic Acids with Other Functional Groups Dichloropropane, 1,2 under Saturated Alkyl Halides Dichlorotrifluoroethane HCFC-123 under Saturated Alkyl Halides Dieldrin under Dihalogenated and Polyhalogenated Ethers... 

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. 

Although substituted phenols (e.g., para-iodophenol, para-phenylphenol, firefly luciferin, coumaric acid) are popular enhancers, in both luminol and acridan ester oxidation, enhancers with other functional groups [24], e.g., phe-nylboronic acids [25-28], phenothiazines [29], are also useful. As an example the structure of the phenothiazine enhancer used in the Supersignal substrate family is shown in Figure 6. 

These protocols were applied to pyridines, quinolines, and naphthyridines. They are compatible with other functional groups, for instance, acid derivatives. Dehydration can be effected by a chemical process (chlorinating agents), or simply by heating. Method A3 generally required harsh conditions, since in most examples no base was added for HC1 consumption, therefore lowering the reactivity of the pyridine nitrogen, present as its hydrochloride salt. 

This hydrogen bonding capacity expressed by the polar selectivity is not limited to an increase in retention for phenols. Packings with embedded polar groups that excel in this feature also exhibit increased retention for analytes with other functional groups. Specifically, carboxylic acids at acidic pH and with acetonitrile as the organic modifier and compounds with sulfonamide functions at acidic and neutral pH exhibit significant... 

Numerous examples of modiflcations to the fundamental cyclodextrin structure have appeared in the literature.The aim of much of this work has been to improve the catalytic properties of the cyclodextrins, and thus to develop so-called artificial enzymes. Cyclodextrins themselves have long been known to be capable of catalyzing such reactions as ester hydrolysis by interaction of the guest with the secondary hydroxyl groups around the rim of the cyclodextrin cavity. The replacement, by synthetic methods, of the hydroxyl groups with other functional groups has been shown, however, to improve remarkably the number of reactions capable of catalysis by the cyclodextrins. For example, Breslow and CO workersreported the attachment of the pyridoxamine-pyridoxal coenzyme group to beta cyclodextrin, and thus found a two hundred-fold acceleration of the conversion of indolepyruvic acid into tryptophan. 

The ring-opening of oxiranes, leading to the formation of isomeric carbonyl compounds by the action of acid catalysts as a result of rearrangement, is of continuing interest (refs. 1-4). However, most of these studies focus mainly on the transformations of terpene oxides or oxiranes with other functional groups in the liquid phase, under homogeneous reaction conditions. 

Pettitt and Stouffer [59] described the use of isopropyl esters, prepared by reaction with 2-bromopropane and sodium hydride, for the GC of amino acids. The above reagent also reacts with other functional groups, which can be of practical significance for the... 

Values of pKa are about 5 (Va = 10-5) for simple carboxylic acids. For example, acetic acid has a pKa of 4.7 (Ka = 1.8 X 10-5). Although carboxylic acids are not as strong as most mineral acids, they are still much more acidic than other functional groups we have studied. For example, alcohols have pKa values in the range 16 to 18. Acetic acid (pKa = 4.74) is about 1011 times as acidic as the most acidic alcohols In fact, concentrated acetic acid causes acid burns when it comes into contact with the skin. 

Most resolution is done on carboxylic acids and often, when a molecule does not contain a carboxyl group, it is converted to a carboxylic acid before resolution is attempted. However, the principle of conversion to diastereomers is not confined to carboxylic acids, and other functional groups may be coupled to an optically active reagent. Racemic bases can be converted to diastereomeric salts with active acids. Alcohols can be converted to diastereomeric esters, aldehydes to diastereomeric hydrazones, and so on. Amino alcohols have been resolved using boric acid and chiral... 

Although infrared absorption intensities are very sensitive to molecular orientation, deriving quantitative information about molecular orientation is not easy [33,34], On the other hand, photoelectron diffraction is relatively easily interpreted to yield adsorbate orientations on surfaces. X-ray photoelectron diffraction and density functional theory calculations have been used in tandem to study the orientations of D- and L-cysteine adsorbed on the Au(17, 11, 9) surface (Fig. 4.9) [35]. Cysteine is an amino acid with the functional group R = CH SH. On the gold surface the S-H bond dissociates to give a thiolate bond to the surface. X-ray photoelectron diffraction of the N Is level indicates that the N-C bond in o-cysteine is oriented roughly parallel to the step edge on the Au(17, 11, 9) surface while the N-C bond in... 

Conversion of a carboxylic acid to a thiohydroxamate ester, followed by heating the product in the presence of a suitable hydrogen donor such as tri-n-butyltin hydride, produces a reductive decarboxylation. This sequence of reactions is called the Barton decarboxylation reaction and may be used to remove a carboxylic acid and replace it with other functional groups. 

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