Conversion to amides

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. 

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... 

The phosphinic isocyanates (116) and isothiocyanates (117) react with oxygen, nitrogen, and phosphorus nucleophiles by attack at carbon rather than phosphorus. Phenyl phosphonodichloridate has been recommended as a useful reagent for the activation (presumably by mixed anhydride formation) of carboxylic acids for conversion to amides and hydrazides. ... 

Acylation of the C3 position can also be accomplished with acid chlorides, as illustrated in the synthesis of indole 7.34, a drug for the treatment of depression. Reaction of indole 7.31 with oxalyl chloride affords C3-substituted product 7.32 even though the benzene ring is very electron-rich. Conversion to amide 7.33 is followed by reduction with lithium aluminium hydride which removes both carbonyl groups, affording the target indole 7.34. 

Olefins, addition—Continued of diazoacetic ester, 498 of halo ethers, 232 of halogen, 106 of hydrogen cyanide, 603 of hydrogen halide, 105 of hypohalous acid, 109 of polyhalides, 107 to cyanides, 571 allylic bromination, 36, 104 condensation, with halides, 108 with phenols, 179 conversion to amides (Wi 11 gerodt),... 

Aromatic amines are less basic than aliphatic amines and the basicity is influenced by substituents on the aromatic ring. The reactivity of amines is modified by conversion to amides such as acetanilide. These still undergo electrophilic attack in the ortho and para positions. 

Conversion to Amides. V-Acyloxazolidinones may be converted to the primary amide via the corresponding hydrazide. Alternatively, trimethylaluminum/amine adducts form active transaminationreagents, providing amides of p-hydroxy acy-loxazolidinones through intramolecular amine addition of the aminoaluminum species (eq 65). ... 

With simple carboxylic acids and amines, direct conversion to amides takes place at elevated temperatures (equation 1). Generally, this reaction may be catalyzed by acid ° or by cation exchange resin. Addition of ammonium carbonate or urea as a source of ammonia reduces reaction temperatures and improves yields. 

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