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Condensation of amides

Formally analogous to the foregoing Grignard additions are the intramolecular condensations of amides with aromatic systems, found in the Bischler-Napieralski reaction 101), which is of particular interest in isoquinoline and indole alkaloid syntheses (102). Condensations of amidines with reactive methylene compounds also led to enamines (103-106). [Pg.324]

Substituted 1,2,4-triazines were conveniently prepared in one pot by the condensation of amides and 1,2-diketones followed by cyclization with hydrazine hydrate <06MI67>. [Pg.415]

Examples of the condensation of amides with aldehydes were also known at this time. Roth and Schuster, working in Strecker s laboratory, had prepared benzylidene diacetamide and anisylidene diacetamide by heating the aldehydes with acetamide. Von Richter in 1872 reported that Tawildarow obtained ethylidene diacetamide by heating acetaldehyde and acetamide, and Nencki obtained ethylidene dibenzamide by carrying out a similar reaction in the presence of hydrochloric acid. [Pg.132]

Synthesis of a, i-Didehydro-u-amino Add Derivatives by Condensation of Amides... [Pg.641]

Scheme 6 Condensation of Amides or Nitriles with a-Oxo Acids O... Scheme 6 Condensation of Amides or Nitriles with a-Oxo Acids O...
Oxidation of SeC 144 derivatives also generates AAla derivatives. Hoffmann degradation of u,p-diaminopropanoic acid, 145 Bergmann s re action11461 of condensation of amides with pyruvic acid, N-hydroxylation followed by dehydration, 147 and N-chlorination/dehydro-chlorination 122-124 have also been used for the synthesis of AAla derivatives. [Pg.651]

PELLIZZARI REACTION. Formation of substituted 1,2,4-triazoles by die condensation of amides and acylhydrazines. When the acyl groups of the amide and acylhydrazine are different, interchange of acyl groups may occur, widi formation of a mixture of triazoles. [Pg.1221]

In contrast, morpholine enamines from higher alkyl ketones do not dimerise but undergo disproportionation to the reduced enamine and various oxidation products. Aldehyde enamines dimerise, but with more difficulty at higher temperatures544. Cross-conjugated545 and linear dienamines (e.g. 132)546 have been prepared by condensation of amide acetals with alkynyl alcohols (equation 37). [Pg.498]

In a versatile single-step convergent procedure, Movassahi et al. described the synthesis of azaheterocycles including multisubstituted quinolines <07JA10096>. One example from their study shows the direct condensation of amide 96 and n-nucleophiles 97 to give the desired multisubstituted quinoline 98. [Pg.304]

A reaction analogous to the condensation of amides with 2-pyrazolin-5-ones is the reaction of amidines first reported by Dains (eq. 29).348,349 This has been extended by Ogata, Tauno and Nishida1070 to vinylogs of amidines of the type C6H5NH(CH==CH)2CH=NC6H5. [Pg.39]

Condensation of 2-amino-l,8-naphthyridine-3-carboxamide 400 with aromatic aldehydes in glacial acetic acid affords 2-aryl-l,2,3,4-tetrahydropyrimido[4,5-Z>][l,8]naphthyridin-4-ones 401, whose oxidation with nitrobenzene in glacial acetic acid gives 2-arylpyrimido[4,5-Z>][l,8]naphthyridin-4(3//)-ones 402. Compounds 402 were also synthesized without isolation of naphthyridones intermediate 401 formed by condensation of amide 400 with aromatic aldehydes on refluxing in a mixture of nitrobenzene and glacial acetic acid (1987IJC(B)1194). [Pg.254]

The simplest apparent approach to enamidophosphonates, albeit in modest yields, (12-20%) is the anhydrous acid-catalysed condensation of amides with diethyl acetylphos-phonate (equation 103). ... [Pg.700]

Amberlyst A-26 The polymeric ba.se is needed to promote the Dieckmann condensation of amid ester I affording pytTolidinone II and for the purification of the condensation product as II remains attached to the resin (cf. Scheme 1.6.26) ... [Pg.71]

Formation of C-N bond has raised of interest in the scientific community in the last 10 years. In this context, the formation of enamides is a valuable protocol. In addition to conventional approaches that include condensation of amides and aldehydes, addition of amides to alkynes, acylation of imines, Curtius rearrangement of a,jS-unsaturated acyl azides, amide Peterson olefination, and Wittig and Horner-Wadsworth-Emmons reactions, several transition metal-catalyzed methods have been developed that allow the synthesis of enamides.Inspired by the analogous arylation of amines catalyzed by palladium or copper complexes (Buchwald-Hartwig reaction), a new approach for the synthesis of enamides has been published recently, which allows to prepare enamides from readily available starting materials (amides and vinyl halides) proceeding under very mild conditions. Thus, we decided to test the Porco-Buchwald amidation of vinyl halides in our synthesis [144-146]. [Pg.133]


See other pages where Condensation of amides is mentioned: [Pg.111]    [Pg.147]    [Pg.77]    [Pg.62]    [Pg.641]    [Pg.111]    [Pg.597]    [Pg.111]    [Pg.293]    [Pg.734]    [Pg.193]    [Pg.322]    [Pg.1243]    [Pg.331]    [Pg.155]    [Pg.320]    [Pg.313]   
See also in sourсe #XX -- [ Pg.237 ]




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Amide condensation

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