Solid amides

Doubts have been cast on these conclusions by Janssen (1961) and Cook (1964), who studied infrared spectra of the salts of dimethyl-acetamide. The strong C=0 band in the solid amide appears at 1639... 

Amides react in certain cases to form ammonium salts of sulfonated amides (22). For example, treatment with benzamide yields ammonium A-benzoylsulfamate [83930-12-5], C5H5C0NHS03 NH4, and treatment with ammonium sulfamate yields diammonium imidodisulfonate [13597-84-1], HN(S020NH4)2. Ammonium sulfamate or sulfamic acid and ammonium carbonate dehydrate liquid or solid amides to nitriles (27). 

G. C. Pimentel (Berkeley) In rebuttal of Dr. Rowlinson s remark that the gas-phase measurements should be given more weight than other types of measurements, we must remember that the measurements made in different phases may not give the same answer, nor may they refer to the same species. This is suggested by the unexpectedly high values of ZlH of H-bond formation shown by Dr. Davies for solid amides. While this AH may include certain interactions not present in the gas phase, and while it may be more difficult to interpret, nevertheless it is the AH appropriate to the solid structure and one cannot determine this value by gas-phase studies. Similarly, in the liquid phase there may be different processes or species than in the gas phase. Hence one cannot discard a measurement of AH of dimerization applicable to solution phase solely because it disagrees with measurements applicable to the gas phase. 

This conclusion is supported by observations of the isomerization of unsaturated hydrocarbons catalysed by potassium amide not only in ammonia solution (Shatenshtein and Vasil eva, 1954 Shatenshtein et al., 1954) but also by solid amides of alkali and alkaline-earth metals (Shatenshtein et al., 1958a). For example, diallyl rearranges to dipropenyl, pentene-1 to pentene-2, and 2-methylbutene-l to 2-methyl-butene-2. Subsequently, a further number of examples of isomerization... 

SYNTHESIS To a well-stirred, ice cold solution of 5.0 g indole in 75 mL TBME, there was added a solution of 6.35 g oxalyl chloride in 25 mL CH2CI2. dropwise, over the course of 15 min. Stirring was continued for an additional 10 min, and the resulting solids were removed by filtration and washed with 15 mL cold TBME. This solid amide was, in turn, added portionwise over a period of 10 min to a well-stirred, ice cold solution of 15 mL N-buty 1-N-methyl amine in 100 mL CH2CI2. The clear, red solution that resulted was stirred for a few additional minutes, washed in sequence with H2O, % aqueous hydrochloric acid, and then H2O. Following... 

Doubts have been cast on these conclusions by Janssen (1961) and Cook (1964), who studied infrared spectra of the salts of dimethyl-acetamide. The strong C=0 band in the solid amide appears at 1639 cm-1. In the solid hydrochloride a band appears at 1693 cm-1, which was assigned to the C=N bond in the O-protonated cation (Janssen, 1961), but could equally be due to the C=0 vibration in the N-protonated cation. Raman spectra of dimethylacetamide (2 m ) in cone, hydrochloric acid show the same intense band at 1693 cm-1 (de Loze et al., 1972). In view of the high concentrations of both the amide and the acid, it is probable that the amide is present in these solutions largely as the O-protonated cation, so that the assignment of this band to the C=N frequency seems likely, especially for a tertiary amide. Infrared and Raman spectra are thus capable of interpretation in terms of both N- and O-protonation, depending to some extent on the amide (primary, secondary or tertiary),. and cannot provide unambiguous evidence for the site of protonation. 

CHEMICAL PROPERTIES noncombustible solid reacts vigorously with acids and hot water hydrolyzes in hot acid solution elevated temperatures cause a highly exothermic reaction with water dehydrates liquid or solid amides to nitriles liberates ammonia at elevated temperatures and forms imidodisulfonates forms addition products with formaldehyde and aldehydes readily oxidized by bromine and chlorine has flame retardant properties because heat decomposition produces non-inflammable gases decomposes at 200°C (392°F) at 760 mmHg FP (N/A) LFL/UFL(N/A) AT (N/A). 

Little dichroism was shown at 1658 cm in the polymers containing more amide groups. The magnitude of this band was probably due to the additional absorbance of hydrogen-bonded side-chain amide groups that absorb in the region of 1650 cm (Bellamy, 1956). The position of this band lends support to the presence of side-chain amide associations in the solid amidated polymers. 

Solid amides from MEA and DEA can be chill flaked, but during formulation the mixture must be heated to 50-70°C for effective incorporation, whereas liquid DEA amides are stored and transported at <50°C, and are easier to incorporate at lower formulation temperatures. A variety of blends have been developed where high-melting amides are incorporated into aqueous anionic surfactant products such as the typical mixture of neutral alcohol sulfate and alcohol ether sulfates used in shampoo products, providing improved ease of transport, storage, and dilution, even at nearambient temperature. 

Attach the vial to an air condenser and warm the solution on a sand bath while stirring at 50-60 °C for approximately 45 min. To the cooled reaction mixture add 1-2 mL of cold water, and then collect the solid amide by vacuum filtration. 

Solid amide used in powdered dlshwash and bath toiletry formulations. Produces brittle, dry residue for carpet shampoo applications. 

A total of 13.7 g. of crude amide obtained directly from several runs as described above can be hydrolyzed to the free acid by the following procedure The solid amide is dissolved in 200 cc. of glacial acetic acid in a 1-1. round-bottomed flask. Concentrated hydrochloric acid (100 cc.) is cautiously added to the boiling solution through the reflux condenser. The solution, containing a little suspended material, is refluxed for seventy-five minutes, after which the addition (through the condenser) of 100 cc. of concentrated hydrochloric acid causes the precipitation of crystals of the acid. After the mixture has been chilled for several hours, 13.4 g. of crude acid (98%) is obtained, by filtration m.p. 223.5-225 (cor.). The acid is purified by treatment of the aqueous solution in dilute potassium hydroxide with Norit and Filter-Cel, followed by precipitation of the free acid and recrystallization from chlorobenzene. The first crop of crystalline acid amounts to 12.3 g. (90%) m.p. 227.5-228 (cor.) in an evacuated tube. 

Amide Formation.—i cc. or 0.5 g. of ester is added to 10 cc. of concentrated ammonia water in a half-ounce bottle, and the suspension observed during several minutes with occasional shaking. If there is no evidence of rapid reaction, the flask is set aside for several hours or until the following day. When working with esters, extremely insoluble in water, a few cc. of alcohol may be added to facilitate reaction. The solid amide is filtered off and crystallized from water or alcohol. 

The jt-jt amide band was observed at 190 nm, and another band below 165 nm was found to become strong as the number of methylene unit however, the assignment of the latter band has not been clear in the solid state or condensed phase. Unfortunately, most theoretical works on the solid amides and polyamides... 

Figure 5 Relationship between Katrp and structure of alkyl halide initiators, measured with Cu X/fPMA (X=Cl or Br) as catalyst with MeCN as solvent at 22 °C 3° red, 2° blue, 1° black R-Br solid, R-CI open, R bottom-half solid Amide , Phenyl , Ester , Nitrile o. Phenyl-ester 0, Allyl . Reprinted from Tang, W. Kwak, Y. Braunecker, W. etal. J. Am. Chem. Soc. 2008, 130,10702-10713, " with permission from the ACS.

With gaseous amines, the addition techniques mentioned under acyl halide reactions may be applied. With liquid amines, the preparation of A-ethylperfluorobutyramide may serve as a model synthesis. As to final purification procedures, solid amides may be recrystallized (alcohol, alcohol-water, petroleum ether, etc. are typical solvents), or, in many cases, distilled under reduced pressure. Liquid amides are best purified by distillation. 

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