Carboxylic acids carboxamide synthesis

H-Chromene, 2-ethyl-3-phenyl-synthesis, 3, 764 4H-Chromene, 2-phenyl-synthesis, 3, 763 4H-Chromene, 2,4,4-trimethyl-addition reactions, 3, 669 2 H-Chromene-3-carboxamide reduction, 3, 675 2H-Chromene-3-carboxylic acid methyl ester alcoholysis, 3, 668... 

Imidazole-5-carboxamide, l-methyl-4-nitro-mass spectra, 5, 359 Imidazole-4-carboxanilide, 1-methyl-synthesis, 5, 435 Imidazolecarboxylic acid, vinyl-polymers, 1, 281 Imidazole-2-carboxylic acid chlorination, 5, 398 mass spectra, 5, 360 synthesis, 5, 474... 

Pyrrole-2-carboxamide, N,N-dimethyl-conformation, 4, 194 Pyrrole-3-carboxamide, N,N-dimethyl-conformation, 4, 194 Pyrrolecarboxamides synthesis, 4, 242 Pyrrole-2-carboxamides synthesis, 4, 148, 360 Pyrrolecarboxylhydrazides Curtius degradation, 4, 362 Pyrrole-2-carboxylic acid, l-benzyl-3-hydroxy-ethyl ester... 

The addition of Grignard reagents to aldehydes, ketones, and esters is the basis for the synthesis of a wide variety of alcohols, and several examples are given in Scheme 7.3. Primary alcohols can be made from formaldehyde (Entry 1) or, with addition of two carbons, from ethylene oxide (Entry 2). Secondary alcohols are obtained from aldehydes (Entries 3 to 6) or formate esters (Entry 7). Tertiary alcohols can be made from esters (Entries 8 and 9) or ketones (Entry 10). Lactones give diols (Entry 11). Aldehydes can be prepared from trialkyl orthoformate esters (Entries 12 and 13). Ketones can be made from nitriles (Entries 14 and 15), pyridine-2-thiol esters (Entry 16), N-methoxy-A-methyl carboxamides (Entries 17 and 18), or anhydrides (Entry 19). Carboxylic acids are available by reaction with C02 (Entries 20 to 22). Amines can be prepared from imines (Entry 23). Two-step procedures that involve formation and dehydration of alcohols provide routes to certain alkenes (Entries 24 and 25). 

Applications of the cross-metathesis reaction in more diverse areas of organic chemistry are beginning to appear in the literature. For example, the use of alkene metathesis in solution-phase combinatorial synthesis was recently reported by Boger and co-workers [45]. They assembled a chemical library of 600 compounds 27 (including cisttrans isomers) in which the final reaction was the metathesis of a mixture of 24 oo-alkene carboxamides 26 (prepared from six ami-nodiacetamides, with differing amide groups, each functionalised with four to-alkene carboxylic acids) (Eq.27). 

Solid-phase synthesis of biomolecules, of which peptides are the prime example, is well established. The search for more effective therapeutic agents creates a need for different strategies to synthesize peptides with C-terminal end groups other than the usual carboxylic acid and carboxamide functionalities. Methods described herein are readily generalized to small nitrogen-containing organic molecules. 

Davidson s synthesis consists of the cydization of a-acyloxyketones with ammonia or ammonium acetate to give 2,4,5-trisubstituted oxazoles. The Passerini reaction between arylglyoxals, carboxylic acids, and isocyanides afforded N-substituted 2-acyloxy-3-aryl-3-oxopropionamides 83 in high yields. Upon heating with an excess of ammonium acetate in acetic acid, compounds 83 were cydized to N,2,4-trisubstituted oxazole-5-carboxamides 84 in fair yields [59]. A large number of a-acyloxy-jS-ketoamides can be prepared by changing the reaction components, so the method provides straightforward access to a variety of oxazole-5-carboxamides (Scheme 2.30). 

A one-pot synthesis of 3,5-disubstituted 7-hydroxy-3//-l,2,3-triazolo[4,5-d]pyrimidines (130) has been carried out by using benzyl azide, cyano-acetamide, ethyl or methyl esters of the appropriate carboxylic acid, and sodium ethoxide as catalyst. The reaction proceeds via a 5-amino-l-benzyltriazole-4-carboxamide intermediate (85JHC1607). 7-Amino-3H-l,2,3-triazolo[4,5-d]pyrimidines 133 (R2 = H) were prepared starting from benzyl azide, malononitrile, and an aliphatic or aromatic nitrile, or by reaction of 130 with phosphorus oxychloride followed by amination. Compound 132 was formed in most reactions from two molecules of the 5-amino-4-cyano-l-benzyltriazole intermediate by an intermolecular nucleophilic at-... 

Biotransformation can serve as an alternative route towards enantiopure aziridines. (1R,25)-1 -Benzyl- and l-arylaziridine-2-carboxamides were obtained in enantiomerically pure form via kinetic resolution of their racemates by Rhodococcus rhodochrous IFO 15564 catalyzed hydrolysis <07OF521>. Rhodococcus erythropolis AJ270 was reported as an efficient whole cell catalyst for the synthesis of highly enantiopure 5,-l-arylaziridine-2-carboxamides and A-l-arylaziridine-2-carboxylic acids <07JOC2040>. Enantiopure 2-... 

Solid-phase synthesis (SPS) of peptides containing at their C-termini the usual carboxylic acid or carboxamide functionalities is a well-established process the peptide is traditionally attached to the resin through the a-carboxyl group of the C-terminal residue, and synthesis proceeds in the C A direction (1,2). However, synthetic peptides containing modifications at the C-termini are often desired because of their potential therapeutic properties and/or synthetic significance as intermediates in peptide and protein chemistry. Therefore, effective solid-phase methods are needed for the preparation of these peptide targets (3). The present chapter describes backbone amide linker (BAL) strategies (4)... 

Almost all recorded purine syntheses from imidazoles involve the cyclization of 5(4)-aminoimidazole-4(5)-carboxylic acid derivatives especially the carboxamides, thiocar-boxamides, carboxamidines, carboxamidoximes, nitriles and esters. The intermediates used for completion of the purine ring are much the same as have been used for Traube cyclization of diaminopyrimidines (Section 4.09.7.3), especially formic and carbonic acid derivatives, and cyclization generally occurs-under much milder conditions. This feature has been of special value in the synthesis of purine nucleosides from imidazole nucleoside precursors. The resultant purine will have variable substituents at C-2 and C-6 and it is convenient to discuss and classify the various preparations largely in terms of the introduced 2-substituents. The C-6 substituents largely reflect the type of carboxylic acid moiety used and do not vary very much between amino, oxo and thioxo. 

Substituted quinoxaline-2-carboxylic acids can be prepared by reaction of benzene-1,2-diamines with oxopropanedioic acid or with its monocthyl or diethyl ester.The synthesis of quinoxalinccarboxamides has been achieved by condensation reactions involving a,/l-dioxo-carboxamides. The reaction is limited to the oxo carbonyl groups because of the reduced reactivity of the amide carbonyl function. 

Adducts (6) and (7) from amides and chlorophosphoric acid aiyl esters or dichlorophosphoric acid aryl esters respectively are well known. - The adducts are formed in a 1 1 ratio. They have been applied to the synthesis of mixed anhydrides from diarylphosphoric acids and carboxylic acids, as well as mixed substituted esters of pyrophosphoric acid. The adduct formation between primary or secondary carboxamides and dichlorophosphates has been used to prepare nitriles and isonitriles respectively. The adduct from DMF and phenyldichlorophosphate is a useful reagent for the preparation of carboxylic acid esters from the corresponding acids and alcohols, 3-lactams from imines and carboxylic acids," carboxylic acid anhydrides, carboxylic acid esters and thiol esters. Adducts of amides with ester amides or diamides of chlorophosphoric acid have been studied. ... 

The hydrolysis of nitriles promoted by metal centers is well known, namely toward the synthesis of amides (NH2COR), compounds with industrial and pharmacological applications.5 9-11 The dramatic enhancement of the rate of nitrile hydrolysis to carboxamides can be so great that the reaction becomes faster than the subsequent hydrolysis of the amides to carboxylic acids which, without the presence of the metal, is often faster than the former.28... 

Aldehydes, arylideneanilines, carboxylic acids and orthoesters have been used as one-oarbon units for binding the two amino functions of 4-amino-l-alkyl-3-propylpyrazole-5-oarboxamide to give l,6-dihydro-pyrazolo[4,3-<7]pyrimidin-7-ones <05MC619 05JHC751>. A modified efficient synthesis of variably substituted pyrazolo[4,3-<7]pyrimidm-7-ones has been described using a pyrazole-5-carboxylic acid, which was selectively brominated at position 4 and then converted into the carboxamide. Microwave irradiation gave better yields in the conversion of the carboxamides to pyrazolo[4,3-J]pyrimidinones <05JHC1085>. 

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