Amide condensation

Primary amides condense with hydroxybenzaldehydes in a manner similar to amines. This reaction is often conducted in the presence of sodium acetate or an organic base such as pyridine. For example, the reaction of sahcylaldehyde and propionamide produces sahcyhdene propionamide (58). 

We prefer the second as it gives two inoJecules of the same keto-amide. Condensation here is very easy standing (12) in the refrigerator with pyridine as catalyst gives 96% of (10). 

EXAMPLES OF AMIDATION CONDENSATION BETWEEN CARBOXYLIC ACIDS AND AMINES CATALYZED BY (3,4,5-TRIFLUOROPHENYL)BORONIC ACID ... 

Fig. 3 Mechanisms for enzymatic supramolecular polymerisation (a) Formation of supramolecular assembly via bond cleavage, (b) Formation of supramolecular assemblies via bond formation. Examples are shown of biocatalytic supramolecular polymerisation of aromatic peptide amphiphiles via (i) phosphate ester hydrolysis, (ri) alkyl ester hydrolysis, and (iii) amide condensation or reversed hydrolysis using protease...

Fig. 2. Kinetics of cross-linking of chondroitin 6-sulfate, a glycosaminoglycan (GAG), to collagen following exposure to 105 °C under 6.7 Pa (50 mtorr). The mechanism of cross-linking is most probably interchain amide condensation involving e-amino groups of lysyl residues on collagen chains with carboxylic groups on glucuronic acid residues in neighboring GAG chains (From [30] with permission).

Nucleophilic aromatic displacement is invoked for incorporation of the side chain in yet another benzimidazole. Thus, treatment of 2,5-dinitroacetanrlide (52-1) with the anion from mercaptomethylcyclohexane leads to the unusual displacement of one of the nitro groups and the formation of thioether (52-3). This intermediate is then converted to diamine (52-4) by sequential reduction and hydrolysis of the amide. Condensation with the same thiourea derivative as above affords dribenda-zole (52-5) [55]. 

Reaction of lH-imidazole-4-carboxilic acid amide with nitrous acid leads to the diazonium salt (5-diazenyl-l-H-imidazole-4-carboxilic acid amide). Condensation of the diazonium salt with methylisocyanate leads to initial formation of unstable urea which cyclizes under the reaction condition to give 3,4-dihydro-3-methyl-4-oxoimidazo(5,l-d)-l,2,3,5-tetrazine-8-carboxamide (temozolomide). 

For larger cycles, tosylamide or high-dilution amide condensations were mostly used. In addition, cyclization of amines and aldehydes to get Schiff bases (mostly for [2+2] or [3+3] cyclizations) is convenient. Metal template synthesis is useful only in special cases. Polycycles are conveniently prepared from appropriately protected cycles. 

AVASOLs are a range of cationic surfactants of the amide condensate class,... 

This material is an anionic fatty amide condensate, approximately 98% active solids and is useful as a synthetic emulsifier and detergent. 

Fatty amide condensate Acrylic, Polyester, Nylon... 

Fatty acid polygiycol ester Fatty acids source oil xoconut Fatty acids source oihsoya Fatty acids source oil mixed Fatty alcohol/ethylene oxide condensate Fatty alcohol sulfates Fatty amide Fatty amide Fatty amide blend Fatty amides and cationic poly-ethylenes blend Fatty amide condensate Fatty amide condensate wax Fatty amidoquaternary Fatty amine Fatty amine... 

The monoamide 5-oxo-cyclam (43) is prepared from 2,3,2-tet by a Michael addition/amide condensation reaction with (m)ethylacrylate, or by reaction with the bifunctional nucleophile chloroacetyl chloride. 

Drustate [Drew]. TM for a series of cationic fatty amino amide condensates, alkyl sulfates. Use Antistatic agents. 

An alternative route to dialkyl 2-oxoalkylphosphonates is based on the use of Nahm-Weinreb amides. Condensation of Nahm-Weinreb amides with dimethyl 1-lithiomethylphosphonate proceeds readily at low temperature. Compared with the ester route (Section 7.1.2.5.1), the Nahm-Weinreb amide route possesses significant synthetic advantages because only a slight excess of phosphonate carbanion is necessary to afford the P-ketophosphonates in good yields (66-85%). - This approach has been developed in the production of the optically active dimethyl 2-oxo-4-(tert-butyldimethylsilyloxy)-5-(methoxycarbonyl)pentylphosphonate (Scheme 7.30). ... 

Tandem conjugate addition ofenolates and aldol reactions Tandem conjugate addition of chiral amines and aldol reactions Part III - Intermediate is an Unstable Imine or Enamine Intermediate Would Be Formed by Amide Condensation... 

The synthesis of a tricyclic amine by tandem amide condensation and Mannich reaction Alternatives to amide condensations use of sulfur... 

Esterification of starch dialdehyde with chlorosulfonic acid in formamide gave a sulfate ester that could be transformed into an amide and methyl ester.532-536 The classical method of sulfonation, namely, by the action of sulfur trioxide in pyridine, is also applicable.537,538 Hemiacetals of starch dialdehyde result upon treatment with suitable alcohols in the presence of an acidic catalyst. In acetic media amides condensed with the carbonyl groups. Acetylation of starch dialdehyde with acetic anhydride is an obvious reaction. Esters with hexanedioic (adipic) acid were also prepared.537 Starch dialdehyde undergoes etherification with monochloroacetic acid in an alkaline medium.538... 

The anions of N-acyl-2-chloropyridin-3-amines, generated by sodium hydride in dimethylform-amide, condense with. r-(/i-chloroalkyl)-/ /,A -dimethy]amines to afford 1-acyl-4-methyl-l,2,3,4-tetrahydropyrido[2,3-7>]pyrazines 17.17 The reaction presumably proceeds with loss of chloromethane. 

Avivan . [Ciba-Geigy/Dyestuffs] Fatty acid amide condensate softener for cellulosk and synthetic fibers. 

Eccowax. [Eastern Cdor ft Chem.] Substituted fatty amide condensate wax cone, for sdtening textiles. 

NopcochexRA. [Hodrel/Emeiy] Fatty amide condensate ml-sdiuble corrosion inhibitor. 

Trifluorophenyl)boronic Acid-Catalyzed Amide Condensation of Carboxylic Acids and Amines N-Benzyl-4-phenylbutyramide. 

Esters and amides. Condensation of c cohols and amines proceeds via triacyloxy conditions. 

Avivan . [Qba-Geigy/Dyestuffe] Fatty add amide condensate softener to cellulosic and synthetic fibers. 

A direct amide condensation catalyst, 3,5-bis(perfluorodecyl)-phenylboronic acid... 

Table 1 Catalytic activities and recovery of arylboronic acid for the direct amide condensation.

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