Amides from aryl ketones

The Willgerodt Reaction allows the synthesis of amides from aryl ketones under the influence of a secondary amine and a thiating agent. The mechanism involves the formation of an enamine which undergoes thiation, and the carbonyl group migrates to the end of the chain via a cascade of thio-substituted iminium-aziridinium rearrangements. 

Carboxylic acid amides from aryl ketones COAr CONHa... 

N-Aroylsulfonic acid amides from aryl methyl ketones... 

The palladium-catalyzed carbonylation of aryl halides in the presence of various nucleophiles is a convenient method for synthesizing various aromatic carbonyl compounds (e.g., acids, esters, amides, thioesters, aldehydes, and ketones). Aromatic acids bearing different aromatic fragments and having various substituents on the benzene ring have been prepared from aryl iodides at room temperature under 1 atm... 

By far one of the most important reactions through the S l mechanism is formation of a C—C bond by the reaction of aryl halides with carbanions derived from hydrocarbons, ketones, esters, amides, nitriles and even, with some limitations, from aldehydes. The reactions of cyanide ions and carbonyl complexes of Co and Fe also form a new C—C bond. 

The formation of an a-chloroenamine 1, which underwent ring contraction to a bicyclo-[3.1.0]hex-6-yliminiumion 2, has been suggested as a likely pathway similar intermediates have been considered to be involved in the formation of Favorskii amides in the reaction of a-halo-a -aryl ketones with secondary amines (for related ehemistry see Seetions 5.2.3.3.-3.4.). Indeed, the A, 7)f-dimethylcyclopropiminium ion was prepared from cyclopropanone via 1,1 -bis(dimethylamino)cyclopropane. ... 

These are stable compounds which do not polymerise or autoxidise. For the most part, pyrrole-aldehydes and -ketones are typical aryl-ketones, though less reactive - such ketones can be viewed as vinylogous amides. They can be reduced to alkyl-pyrroles by the Wolff-Kishner method, or by sodium borohydride via elimination from the initial alcoholic product (cf. 16.11). Treatment of acyl-l-phenylsulfonyl-pyrroles with f-butylamine-borane also effects conversion to the corresponding alkyl derivatives. ... 

Alkyl and arylmagnesium halides react with 2-methylquinoxaline by addition of one mole of reactant to the 3,4-bond. After hydrolysis the 2-alkyl- or 2-aryl-l,2-dihydro-3-methylquinoxalines (52) are obtained. When ethylmagnesium bromide is used a dimeric by-product (53) is also isolatedReaction of 2,3-dimethylquinoxaline with benzonitrile and lithium amide gives l-amino-l-phenyl-2-(3-methyl-2-quinoxalinyl)-ethylene (54). The mono- and dilithium salts of 2,3-dimethylquinoxaline have been generated from the quinoxaline by reaction with one or two equivalents of lithium diisopropylamide (LiNPr, respectively. These salts have been reacted with a variety of electrophilic reagents such as alkyl halides, aryl ketones, esters, and nitriles. " ... 

OAr From PTBD-resin (cf. Table 1.6.7, polymeric bases) by treatment with ArOH in MeCN.198 Alkyl aryl ethers from primary, allylic and benzylic bromides as well as from a-bromo ketones, esters and amides. Bis-aryl ethers from aryl fluorides. ... 

Recent advances in organometallic chemistry have led to development of various novel methods in synthetic organic chemistry. A Pd-catalyzed reaction has been a particularly useful method. In these reactions, Pd-catalyzed carbonylation is a very attractive method because one carbon is elongated from various functional groups, such as aryl halide, alkyl halide, allyl acetates, allyl carbonates, and even the keto-carbonyl groups, to form esters, amides, and unsaturated ketones (Scheme 1). 

The preparation of aryl ketones can be achieved starting from benzoic acids and nitriles (as the reaction medium) under Pd catalysis via the ketimine intermediates (Scheme 22.11) [20a]. A similar protocol has been developed for the synthesis of aryl amidines replacing the nitrile with a cyan-amide [20b]. 

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