Amides boiling point

Polymerization Solvent. Sulfolane can be used alone or in combination with a cosolvent as a polymerization solvent for polyureas, polysulfones, polysUoxanes, polyether polyols, polybenzimidazoles, polyphenylene ethers, poly(l,4-benzamide) (poly(imino-l,4-phenylenecarbonyl)), sUylated poly(amides), poly(arylene ether ketones), polythioamides, and poly(vinylnaphthalene/fumaronitrile) initiated by laser (134—144). Advantages of using sulfolane as a polymerization solvent include increased polymerization rate, ease of polymer purification, better solubilizing characteristics, and improved thermal stabUity. The increased polymerization rate has been attributed not only to an increase in the reaction temperature because of the higher boiling point of sulfolane, but also to a decrease in the activation energy of polymerization as a result of the contribution from the sulfonic group of the solvent. 

If 2-n-propyl-3-methyl-3-isobutyloxaziranc is allowed to boil under nitrogen, the boiling point is lowered to 128°C from the initial 168°C within 2 hr. Methyl isobutyl ketone (0.92 mole), ammonia (0.32 mole), and a little amide (0.04 mole) are formed [Eq. (29)]. ... 

The amino interchange reaction is another method commonly used for preparing phosphinous amides [67] (Scheme 9). The low boiling points of di-methylamine and diethylamine allow their displacement from Ar,AT-dimethyl and AT,iV-diethyl phosphinous amides, respectively, by other less volatile amines, leading to new members of the same class. High reaction temperatures are nevertheless required. 

A recent report [6] has discussed the effect of monomode microwave irradiation in the palladium-catalyzed phenylation of 5-iodouracil 4 with the nontoxic sodium tet-raphenylborate 5 as phenyl reagent (Scheme 8.3). The authors showed that the use of monomethylformamide (MMF) as solvent increases the yield of 6 (70%), because MMF has a high boiling point (180 °C) and is more polar (s = 182.5) than other amides used in microwave-activated reactions. 

Apart from the first member of the series, formamide, HCO.NH2, which is a liquid, the amides are colourless crystalline solids. The lower members are readily soluble in water and the higher ones can generally be recrystallised from hot water. The boiling points are much higher than those of the corresponding acids ... 

Melting and boiling points Primary amides have much higher melting and boiling points than carboxylic acids. Many simple amides are solid at room temperature. 

The compositions consist of a heat-plastified mixture of an ethylene homopolymer or copolymer, about 3 to 30 pbw of an elastomer, a stability control agent, which is a partial ester of a long chain fatty acid with a polyol, higher allyl amine, fatty acid amide or olefinically unsaturated carboxylic acid copolymer, and a hydrocarbon blowing agent having from 1 to 6 carbon atoms and a boiling point between -175 and 50C. 

Nonanoyl morpholide—pelargonic morpholide or EA 1778—is a fatty acid amide with a molecular weight of 227 and a boiling point of 120-130°C at 0.5 mm Hg (see Table 4-1). Classed as a pungent, because of Its pungent odor, It Is chemically related to alkaloids found In black pepper.1 3 4 it8 synthesis has been described by Rice et al.3... 

If a brownish color or a wide range of the boiling point of the main fraction is observed, redistillation is recommended. Redistillation is necessary for (2S,3S)-2-chloro-3-methylpentanoic acid. Yields are given in Table. Enantiomeric purities (see Table) were determined after conversion to tert-butyl amides (catalyzed by dicyclohexylcarbodilmide, 30 min at 0°C in... 

BECKMANN, ERNST (1853-1923). Beckmann was a German chemist who discovered in 1886 the arrangement of oximes of ketones into acid amides or anilides, named the Beckmann molecular transformation. He was the inventor of two pieces of apparatus used in determining freezing and boiling points of solutions. The Beckmann thermometer is used for determining molecular weights in solutions. 

The fact that under the same conditions acetophenone oxime does not form amides, but remains intact, also provides evidence against the classical Beckmann rearrangement. The conditions found can be employed for preparing amides from nitriles and aldoximes, especially when the latter contain fragments unstable to acids. In the absence of DMSO, benzaldoxime is dehydrated with alkali only at the boiling point (200°C). 

McKay and Latham (1981) have also determined compound class distributions in the high-boiling distillates and the residua for four crude oils. As shown in Table VIII, the content of heteroatom compounds increases with increasing boiling point. The 675°C+ residuum may have nearly 10 times the acids, bases, or neutral Lewis (pyrrolic and amides unreactive to column resins) bases compared to the VGO portion (370-535°C). Grizzle et al. (1981) have also employed compound class separations and have observed similar trends. McKay and Latham (1981) calculated that each acid, base, or neutral nitrogen molecule in the <675°C residuum contains three to five heteroatoms. 

Because of resonance, the C-N bond in amides has considerable C=N character. Rotation about that bond is restricted, and the amide group is planar. Amides are polar, form hydrogen bonds, and have high boiling points considering their molecular weights. 

To a solution of 6.7 g of sodium amide in 100 ml of anhydrous diethyl ether was added dropwise 26 g of 4-isobutylbenzene cyanide while the mixture was stirred and heated under gentle reflux. After all of the 4-isobutylbenzene cyanide had been added, the mixture was heated under gentle reflux for 15 min, after which 23.4 g of ethyl iodide was slowly added dropwise thereto from the dropping funnel. After completion of the addition of the ethyl iodide, the mixture was heated under gentle reflux for an initial period of 15 min, after which it was diluted with an equal volume of water and shaken. The two layers that formed were separated and the aqueous layer was then extracted with two 50 ml portions of diethyl ether. The ether extracts were combined and then washed with two 80 ml portions of water and dried over anhydrous magnesium sulfate. The dried ether extract was then distilled at a subatmospheric pressure. In this manner, 25 g of a clear transparent uncolored liquid having a boiling point of 118-122°C at a pressure of 1mm of mercury, which consisted of 2-(4-isobutylphenyl)butyronitrile, was collected. This yield was equivalent to 83% of the theoretical. 

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