Carboxylic acid amid acetamide

The instability of primary nitramines in acidic solution means that the nitration of the parent amine with nitric acid or its mixtures is not a feasible route to these compounds. The hydrolysis of secondary nitramides is probably the single most important route to primary nitramines. Accordingly, primary nitramines are often prepared by an indirect four step route (1) acylation of a primary amine to an amide, (2) A-nitration to a secondary nitramide, (3) hydrolysis or ammonolysis with aqueous base and (4) subsequent acidification to release the free nitramine (Equation 5.17). Substrates used in these reactions include sulfonamides, carbamates (urethanes), ureas and carboxylic acid amides like acetamides and formamides etc. The nitration of amides and related compounds has been discussed in Section 5.5. 

The carboxylic acid amides most conunonly studied as ligands are formamide, acetamide, and the W-substituted derivatives, particularly A,A-dimethylformamide (DMF). These compounds are often used as solvents and have high dielectric constants, particularly when they contain an N-H bond, and such uses helped to stimulate interest in the amides as ligands. There are two possible donor atoms, N or O, but all complexes of the simple amide ligands, characterized by X-ray structure determination at least, have M-O bonds. The amides are usually terminal ligands but can bridge between metal atoms in some instances. 

Amides. For primary amides the suffix -amide is added to the systematic name of the parent acid. For example, CH3—CO—NHj is acetamide. Oxamide is retained for HjN—CO—CO—NHj. The name -carboxylic acid is replaced by -carboxamide. 

A/,0-Bis(trimethylsilyl)trifluoroacetamide. This reagent is suitable for the silylation of carboxylic acids, alcohols, phenols, amides, and ureas. It has the advantage over bis(trimethylsilyl)acetamide in that the byproducts are more volatile. 

Carboxylic Acids, R—C02H 0 // ch3—c OH ethanoic acid (acetic acid) Esters, R—C02R 0 // ch3—c 0—ch3 methyl ethanoate (methyl acetate) Amides, R—CONH2 P CH3—c nh2 ethanamide (acetamide) ... 

This section deals with the coordination chemistry of amides of carboxylic acids, predominantly formamide, acetamide and their -substituted derivatives. Lactams are also mentioned briefly. 

R—C—N— II 1 0 H Amide CH3C—N—H 11 1 0 H ch3ch2cnhch3 0 Acetamide or Ethanamide N-Methylpropan amide -ic or -oic acid to -amide or -carboxylic acid to carboxamide... 

Cyclic anhydrides react well with trimethyl(trifluoromethyl)silane however, a stoichiometric amount of tctrabutylammonium fluoride is required. - For example, succinic anhydride undergoes efficient addition of trimethyl(trifluoromethyl)silane to initially form an adduct, which upon hydrolysis aflbrds the trifluoromethyl-substiluted 0x0 carboxylic acid 27. Simple amides, such as benzamide and acetamide, do not react with trimetliyl(trifluoromethyl)silane even when a molar quantity of tetrabutylainmonium fluoride is used. Furthermore, lactams, such as caprolactam, do not react with trimethyl(trifluoromethyl)silane under similar conditions. An activated amide carbonyl, such as that in A -methylsuccinimide. however, reacts smoothly to afford an interesting adduct, which upon acid hydrolysis affords the hcmiaminal 28. 

Bis(trimethylsilyl)acetamide (1). Mol. wt. 203.44, b.p. 71-73735 mm. Prepared in 80% yield by reaction of acetamide with trimethylchlorosilane with triethylamine as catalyst, the reagent effects trimethylsilyUuion of amides, ureas, amino acids, phenols, carboxylic acids, enols. ... 

A,0-Bis(trimethylsilyl)trifluoroacetamide. This reagent is suitable for the silylation of carboxylic acids, alcohols, phenols, amides, and ureas. It has the advantage over bis(trimethylsilyl)acetamide in that the by-products are more volatile. It has been used for the selective protection of 10-desacetyI-baccatin III using LHMDS as a catalyst. The TES and TBDMS ethers were prepared similarly. Conventional conditions using the silyl chloride results in silylation of the C-7 hydroxyl ... 

Sulfonyl fluorides are readily obtained from sulfonyl chlorides and KF or KHF2j even in an aqueous medium.801"804 Carboxylic acid fluorides are formed when the acid chlorides are heated with dry KF and can be removed continuously from the reaction mixture by distillation through a column formyl and acetyl fluorides are thus obtained when the acid is heated with benzoyl chloride and KF.805,806 Xylene or acetamide may be used as diluent. Further, a>chloro and at-bromo fatty esters, nitriles, and amides react with KF at temperatures around 100-150°. 

The simple amides are named from the corresponding carboxylic acid by dropping the ending "oic acid" or "ic acid" and substituting the ending "amide," For example, acetic acid or ethanoic acid (CH3C-OH) becomes acetamide... 

Amides An amide is an organic compound in which the -OH group of a carboxylic acid is replaced by a nitrogen atom bonded to other atoms. The general structure of an amide is shown in Table 22.11. Amides are named by writing the name of the alkane with the same number of carbon atoms, and then replacing the final -e with -amide. Thus, the amide shown in Table 22.11 is called ethanamide, but it can also be named acetamide from its common name, acetic acid. 

Amides. Despite many investigations in the 1970s and 1980s on Pd-catalyzed a-arylation of carboxylic acid derivatives, that of amides had not been studied until recently. In 1998, the reaction of potassium enolates of 7V,7V-dimethylacetamide (DMA) and other amides with aryl bromides in the presence of catalytic amounts of Pd(dba)2 and bidentate phosphines, such as BINAP and dppf, was shown to provide the desired a-arylated products in up to roughly 70% yields, as shown in Table Diarylation competed with monoaryladon to the extent of up to 18%. Under the conditions used, the intermolecular reactions of amides other than acetamides were rather disappointing, as indicated by the last two entries in Table 5. Clearly, additional development is desirable. Its intramolecular cyclic version, however, is considerably more favorable, as discussed in the following subsection. 

BSA was first reported by Birkofer ef al. in 1963 [40). It is a more potent TMS donor than HMDS or TMSDEA (see below) and is one of the most commonly used silylating reagents. The reactivity of BSA is similar to that of BSTFA and MSTFA (see below), readily silylating non-sterically hindered alcohols, carboxylic acids, amino acids, amides, amines and enols. Although not as volatile as the by-products of silylation using BSTFA, those of BSA (N-trimethylsilylacetamide and acetamide) are sufficiently volatile not to interfere in the majority of GC analyses. 

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