To amide

B). Many nitriles when treated with hydrogen peroxide in warm alkaline solution undergo hydrolysis to amides which can thus be readily obtained in high yield. Insoluble liquid nitriles can be treated directly in the aqueous suspension, but for insoluble solid nitriles the addition of a suitable organic solvent to give a complete solution may be desirable, although the completion of the hydrolysis may not then be so readily detected. 

The most frequent applications of these procedures he in the preparation of terminal alkynes Because the terminal alkyne product is acidic enough to transfer a proton to amide anion one equivalent of base m addition to the two equivalents required for dou ble dehydrohalogenation is needed Adding water or acid after the reaction is complete converts the sodium salt to the corresponding alkyne... 

Amines are convert ed to amides on reaction with acyl chlorides Other acylating agents such as carboxylic acid anhydrides and esters may also be used but are less reactive... 

By analogy to phenols we would expect the isomers with —OH groups on benzene like rings to be more stable This turns out not to be true because the keto forms are also aromatic owing to amide resonance... 

Acylation (Section 12 7 and Chapter 20) Reaction in which an acyl group becomes attached to some structural unit in a molecule Examples include the Fnedel-Crafts acylation and the conversion of amines to amides Acyl chloride (Sections 4 1 and 20 1) Compound of the type... 

Acryhc esters may be saponified, converted to other esters (particularly of higher alcohols by acid catalyzed alcohol interchange), or converted to amides by aminolysis. Transesterification is comphcated by the azeotropic behavior of lower acrylates and alcohols but is useful in preparation of higher alkyl acrylates. 

Esters are named by replacing the ending -ic acid with the suffix -ate. The alcohol portion of the ester is named by replacing the -ane ending of the parent hydrocarbon name with the suffix -yl. The alkyl radical name of an ester is separated from the carboxylate name, eg, methyl formate for HCOOCH. Amides are named by changing the ending -oic acid to -amide for either systematic or common names, eg, hexanamide and acetamide. 

The nitrile groups of these three heterocycHc thiacyanocarbons behave normally and are convertible to amide, imide, or carboxyUc acid groups. 

Nylon resins are made by numerous methods (53) ranging from ester amidation (54) to the Schotten-Baumann synthesis (55). The most commonly used method for making nylon-6,6 and related resins is the heat-induced condensation of monomeric salt complexes (56). In this process, stoichiometric amounts of diacid and diamine react in water to form salts. Water is removed and further heating converts the carboxylate functions to amide linkages. Chain lengths are controlled by small amounts of monofunctional reagents. The molten finished nylon resin can be dkectly extmded to pellets. 

Esters undergo hydrolysis and conversion to amides under the usual conditions, and amide side chains have also been formed from the acid and amine with DCCI. Acids have been formed from the corresponding spirohydantoins via ureido derivatives (Section 2.15.15.6.1), and undergo decarboxylation in the usual manner. 

Aziridinones undergo two types of selective ring opening by nucleophiles <68AG(E)25). Reaction with proton-containing nucleophiles, e.g. water, alcohols, thiols, amines and mineral acids, leads exclusively to amides (339), corresponding to an C —N bond rupture. 

The higher frequencies of the /3-lactam carbonyl absorption in fused systems has been attributed to increased inhibition of amide resonance as the /3-lactam ring becomes less planar (b-72mI50900 p. 303). For the 3-cephems (61) there is also the possibility of enamine resonance which could further reduce the ability of the /3-lactam nitrogen to contribute to amide resonance. 

BECKMANN Rearrangement or fragmentation Acid catalyzed rearrangement of oximes to amides or cleavage of oximes to nitnies... 

The use o< HN3 in the conversion of cartxsxyKc acids to amides, of aldehydes mlo intnies, or ol ketones into tetrazoies or amides (with retention). 

WILLGERODT- KINDLER Rearrangement Rearrangement ot ketones to amides by heating with sulfur and ammonia or amines. 

The section on sulfonamides should be consulted for a related approach to nitrogen protection. Some of the derivatives presented there may also be applicable to amides. 

The conversion of alcohols to esters by O-acylation and of amines to amides by N-acylation are fundamental organic reactions. These reactions are the reverse of the hydrolytic procedures discussed in the preceding sections. Section 3.4 in Part B discusses these reactions from the point of view of synthetic applications and methods. 

Primary and secondary amines, double bonds, aldehydes, sulfides and certain aromatic and dihydroaroraatic systems are also oxidized by chromium VI reagents under standard hydroxyl oxidizing conditions. Amines are commonly protected by salt formation or by conversion to amides. Aldehydes and... 

Ruonnated carboxylic anhydrides and acyl halides as common acylating reagents to convert amines to amides and to acy late suitable heterocyclic nitiogen atoms have already been described in the first edition [10] Like in the acylation at oxygen, much synthetic activity was concentrated m the past few years on the denvatization of biomolecules by fluoroacylation reactions, that is, tnfluoroacetylation of amino sugars,... 

Pyridinethiol, Et3N, CH2CI2, 95% yield. The methylthioamide group is stable to 2.5 N NaOH, THF, H2O and to 10% H2SO4, MeOH, H20. The section on sulfenamides should be consulted for a related approach to nitrogen protection. Some of the derivatives presented there may also be applicable to amides. 

Solutions of alkali metals in liquid ammonia are valuable as powerful and selective reducing agents. The solutions are themselves unstable with respect to amide formation ... 

Application of the Bischler-Napieralski reaction to amides of tryptophan has been investigated. The cyclodehydration of acetyltrypto-phan under conventional conditions proved unsuccessful. Attempted ring closure of acetyltryptophan or its ethyl ester was accompanied by decarboxylation and aromatization, yielding... 

The reaction of diacetylene and its asymmetric homologs (penta-l,3-diyne, hexa-1,3-diyne) with semicarbazide (72ZOR2605) affords the amides of 3-methyl-pyrazole- 1-carboxylic acid (27) (80°C, EtONa, EtOH, 40 h). Amide 26 undergoes irreversible rearrangement to amide 27 at 80°C (EtONa, EtOH). 

Condensation of m-fluorobenzaldehyde with malonic acid leads to the trans cinnamic acid 96 acylation of the acid chloride with cyclopropylaminc leads to amide 97 (cinflumide), a muscle relaxant [24]. 

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