Amide carboxyl and

Alkyl- or 3-aryl-2,4-oxazolidinediones via photochemical cyclization, ° organonickel-mediated carbonylation, ° cyclization of A-alkenyl-a-acet-amides, ° carboxylation and cyclization of 2-propynamides, °" cyclization of (9-carbamates of a-hydroxy acetic acids and esters,cyclization of a-hydroxy acetamides,and catalytic asymmetric dihydroxylation (ADH) of A-alkenoyl-2-oxazolidinones. ... 

The actinides have a high degree of specificity for neutral and anionic oxygen-containing organic molecules. The actinide complexes with O -donor ligands that are most widely studied include alkoxides, aryloxides amide, carboxylates, and oxalates. Complexes with alcohols, ethers, esters, ketones, aldehydes, ketoenolates, and carbamates have also been reported. 

There are several available reports focusing on the NFR soybean protein-based composites for example, Liu et al. [46] evaluated the mechanical properties of grass-reinforced soy-based bioplastic, while Lodha and Netravah [47] evaluated the interfacial strength for ramie fiber-reinforced soy protein isolate (SPI). It must be noted, however, that the long-term performance of soy proteins is Hmited because of their high sensitivity to moisture as a result of the presence of amine, amide, carboxyl, and hydroxyl groups. To reduce their hygroscopicity, the soy proteins are cross-Hnked with aldehydes such as formaldehyde. 

Clark, L. B. Polarization assignments in the vacuum UV spectra of the primary amide, carboxyl, and peptide groups. J. Am. Chem. Soc. 1995, 117, 7974-7986. 

The amino resins can react with several functionalities on the main binder resins such as hydroxyl, amide, carboxyl, and urethane (or carbamate). Most commonly, the binder resins are hydroxyl functional acrylics, polyesters, or modifications of these. Recently, there has been an increase in product offerings and literature references to urethane or carbamate functional resins being paired with amino resins (16-18). The curing reactions require acid catalysis and heat. There is a significant variety of reactivities (and therefore curing temperatures) possible with amino resins, but the lower temperature cure materials... 

Section 27 5 Ammo acids undergo reactions characteristic of the ammo group (e g amide formation) and the carboxyl group (e g esterification) Ammo acid side chains undergo reactions characteristic of the functional groups they contain... 

Hexamethylolmelamine can further condense in the presence of an acid catalyst ether linkages can also form (see Urea Eormaldehyde ). A wide variety of resins can be obtained by careful selection of pH, reaction temperature, reactant ratio, amino monomer, and extent of condensation. Eiquid coating resins are prepared by reacting methanol or butanol with the initial methylolated products. These can be used to produce hard, solvent-resistant coatings by heating with a variety of hydroxy, carboxyl, and amide functional polymers to produce a cross-linked film. 

Chemical Properties. The chemical reactivity of nylon is a function of the amide groups and the amine and carboxyl ends. The aHphatic segment of the chain is relatively stable. 

Reactions of the carboxyl group include salt and acid chloride formation, esterification, pyrolysis, reduction, and amide, nitrile, and amine formation. Salt formation occurs when the carboxyUc acid reacts with an alkaline substance (22)... 

There is also the possibility of removing the 2-oxo group by ring cleavage and subsequent recyclization. Lumazine can be hydrolyzed by strong alkali to 2-aminopyrazine-3-carboxylic acid (153) which is converted first into the amide (154) and then cyclized by ethyl orthoformate into pteridine-4-one (155 equation 47) (51JCS474). 

A-/-Butyldimethylsilyl-7V-methyltrifluoroacetamide, CH3CN, 5 min, 97-100% yield.This reagent also silylates thiols, amines, amides, carboxylic acids, and enolizable carbonyl groups. 

There are large differences in reactivity among the various carboxylic acid derivatives, such as amides, esters, and acyl chlorides. One important factor is the resonance stabilization provided by the heteroatom. This decreases in the order N > O > Cl. Electron donation reduces the electrophilicity of the carbonyl group, and the corresponding stabilization is lost in the tetrahedral intermediate. 

CjHgONa, which is obtained from ricinine by replacement of the methoxyl group by hydroxyl, chlorine and hydrogen in succession. Ricinidine, on hydrolysis, yields first an amide, C7Hg02N, and then a carboxylic acid, by ... 

In —I—M-substituted aminothiophenes, the possibility of coupling during diazotization is eliminated. Thus ethyl 5-amino-2-thiophene-carboxylate and 5-amino-2-thiophenesulfonic acid and its amide- have been diazotized and coupled with various reagents. 

Heating of a mixture of ethyl 9-substituted 7-oxo-7//-pyrido[l,2,3-e/e]-l,4-benzoxazine-6-carboxylates and 4-chlorobenzylamine yielded iV-(4-chlor-obenzyl)amides (01MIP2). 

Closely related to the carboxylic acids and nitriles discussed in the previous chapter are the carboxylic acid derivatives, compounds in which an acyl group is bonded to an electronegative atom or substituent that can net as a leaving group in a substitution reaction. Many kinds of acid derivatives are known, but we ll be concerned primarily with four of the more common ones acid halides, acid anhydrides, esters, and amides. Esters and amides are common in both laboratory and biological chemistry, while acid halides and acid anhydrides are used only in the laboratory. Thioesters and acyl phosphates are encountered primarily in biological chemistry. Note the structural similarity between acid anhydrides and acy) phosphates. 

Surfactants are prepared which contain carboxylic acid ester or amide chains and terminal acid groups selected from phosphoric acid, carboxymethyl, sulfuric acid, sulfonic acid, and phosphonic acid. These surfactants can be obtained by reaction of phosphoric acid or phosphorus pentoxide with polyhydroxystearic acid or polycaprolactone at 180-190°C under an inert gas. They are useful as polymerization catalysts and as dispersing agents for fuel, diesel, and paraffin oils [69]. 

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