Dimethylformamide boiling point

To a solution of 4 g of sodium in 200 ml of n-propanol is added 39 g of homovanillic acid-n-propyl ester (boiling point 160°C to 162°C/4 mm Hg) and the mixture is concentrated by evaporation under vacuum. After dissolving the residue in 200 ml of dimethylformamide and the addition of 0.5 gof sodium iodide, 26.2 g of chloracetic acid-N,N-diethylamide are added drop-wise with stirring at an internal temperature of 130°C, and the mixture is further heated at 130°C for three hours. From the cooled reaction mixture the precipitated salts are removed by filtering off with suction. After driving off the dimethylformamide under vacuum, the product is fractionated under vacuum, and 44.3 g of 3-methoxy-4-N,N-diethylcarbamido-methoxy phenyl acetic acid-n-propyl ester are obtained as a yellowish oil of boiling point 210°C to 212°C/0,7 mm Hg,... 

Due to its commercial importance, the synthesis of copper phthalocyanine (PcCu) is the best investigated of all the phthalocyanines. Copper phthalocyanine is prepared from phthalonitrile and copper(I) chloride without solvent137 and also in a melt of urea.229,277 Additionally, the insertion of copper into metal-free phthalocyanine in butan-l-ol and pentan-l-ol is possible. The copper salts used in this case are copper(I) chloride112 and copper(II) acetate.290 Starting from copper(II) acetate, copper phthalocyanine can also be prepared in ethylene glycol.127 As mentioned above, copper phthalocyanine often occurs as a byproduct of the Rosenmund-von Braun reaction. To increase the yield of the phthalocyanine the solvent dimethylformamide can be substituted by quinoline. Due to the higher boiling point of quinoline, the copper phthalocyanine is the main product of the reaction of copper(I) cyanide and 1,2-dibromoben-zene.130... 

Figs. 12 and 13 show the crystal structure of 6-Gd. Four of the linear POM-catalyst dicarboxylic acid units, 5, are linked by di-lanthanide paddle wheel junctions (Fig. 12) into the open-framework material 96). Fig. 13 shows the large channels in 6-Gd. These are filled with dimethylformamide (DMF) molecules that are hard to remove (the boiling point of DMF at 1.0 atmosphere — 151 °C). Thus while the solvent-accessible internal volume of 6-Gd is 50.5% of the crystal... 

The C4 stream is fed to the middle of a fractionator, and a high boiling point solvent is fed at the top. The solvent, as it works its way down, strips out the butadiene as the C4 vapor works its way up the column. The solvent and butadiene come out the bottom and can easily be split in a second column. Two popular high boiling point solvents are N-methylpyrrolidone (NMP) and Dimethylformamide (DMF). The chapter on benzene has more details on the extractive distillation process. 

It is usual to carry out the reaction in water or ethanol, or in mixtures of the two, at temperatures ranging from 60° to the boiling point, for from 2 to 12 hours. Butanol has also been used as a solvent [82, 136] and, exceptionally xylene [137] and dimethylformamide [138], or even no solvent at all [136] The alkyl mercaptan which is evolved in this reaction can be absorbed in a solution of sodium hydroxide and hydrogen peroxide [135] or in a charcoalicupric chloride trap [139]. The guanidines are often conveniently isolated via their relatively insoluble bicarbonates [118, 139]. 

Vacuum sublimation of a Zn(III) complex solution produced a pink-colored solid, which was Zn(III) perfhiorotetraphenylporphyrin. NMR analysis of this product showed the absence of pyrrole hydrogen atoms, which is the evidence for complete replacement. Then bivalent iron chloride (FeCl2) was prepared according to the common technique [17]. This compound was then used for Zn(III) ion replacement in a porphyrin ring. For this purpose, the Zn(III) complex was dissolved in dimethylformamide (DMF) and then, with the addition of an FeCl2 solution, also in DMF. The reaction mixture was heated in a steam bath at water boiling point for 5 h. Finally, a dark-brown sediment was deposited, and the solution was colored blue, which is typical of iron(III) perfhiorotetraphenylporphyrin (perFTPhPFe(III)) dissolved in DMF. In this case, the active weight of the catalyst iron(III) perfhiorotetraphenylporphyrin equaled 47.05 mg. 

The solution of 3,6-dichlorophthalic anhydride in 300 ml of N,N-dimethylformamide are heated to the boiling point over 15 min with t-butylcarbazate. Subsequent to evaporation of the solvent, N-(t-butyloxycarbonylamino)-3,6-dichlorophthalimide is obtained from ethanol. 

Esters, tertiary amides, and nitriles are frequently used as solvents for organic reactions because they provide a polar reaction medium without O—H or N—H groups that can donate protons or act as nucleophiles. Ethyl acetate is a moderately polar solvent with a boiling point of 77 °C, convenient for easy evaporation from a reaction mixture. Acetonitrile, dimethylformamide (DMF), and dimethylacetamide (DMA) are highly polar solvents that solvate ions almost as well as water, but without the reactivity of O—H or N—H groups. These three solvents are miscible with water and are often used in solvent mixtures with water. 

Linoleic Acid occurs as a colorless to pale yellow, oily liquid that is easily oxidized by air. It is an essential fatty acid and the major constituent of many vegetable oils, including cottonseed, soybean, peanut, corn, sunflower seed, safflower, poppy seed, and linseed. Its specific gravity is about 0.901, and its refractive index is about 1.469. It has a boiling point ranging from 225° to 230° and a melting point around -5°. One milliliter dissolves in 10 mL of petroleum ether. It is freely soluble in ether soluble in absolute alcohol and in chloroform and miscible with dimethylformamide, fat solvents, and oils. It is insoluble in water. 

Special solvent. Newman - recommends N-methyl-2-pyrrolidone as solvent for the reaction of an aryl halide with cuprous cyanide to produce the corresponding nitrile. Dimethylformamide (b.p. 153°) has been suggested as a better solvent than originally used pyridine (b.p. 115°), but l-methyl-2-pyrrolidone has an even higher boiling point and seems still more satisfactory. An example is the synthesis of... 

Low viscosity is important for ease of handling and mixing. Table 1 shows that, with the possible exception of W,iV-dimethylformamide, there is a degree of matching of boiling points and viscosities. When mixed solvents are used, the viscosities of the mixtures are intermediate between the values for the pure components in the mixture. Thus, for a mixture of solvents A and B, the viscosity (tj) of the mixture is given by... 

In order to follow the mutarotation, the sample (5 tL) is quickly dissolved in 2V,A(-dimethylformamide and the solution is cooled in liquid nitrogen. The sily-lating mixture is added, allowed to warm to room temperature, then applied to a column. Used at 15()-200 C, the column contains a liquid with a high boiling point, adsorbed on a powdery solid phase. Utilizing this method, it is possible to observe as many peaks on the chromatogram as there are tautomers in noticeable quantities in solution. Identifying the peaks requires the isolation of fractions in a measurable quantity. 

C under argon. Methanol was removed azeotropically at 56 °C at a fast rate and as the boiling point began to rise, the distillation rate was reduced to 4 drops/min. and heating continued for 15h. The polymer thus prepared precipitated out of cyclohexane. The powdery polymer was crystalline with a melting point (DSC) of 212 °C. It was insoluble in the usual organic solvents such as methylene chloride, chloroform, ether, tetrahydrofuran, ethyl acetate, acetone, dimethylformamide, and dimethylsulfoxide. 

Dimethylformamide up to the boiling point 8 compatible DuPont Teflon PFA... 

Example 15.5. The separation of benzene B from n-heptane H by ordinary distillation is difficult. At atmospheric pressure, the boiling points differ by 18.3°C. However, because of liquid-phase nonideality, the relative volatility decreases to a value less than 1.15 at high benzene concentrations. An alternative method of separation is liquid-liquid extraction with a mixture of dimethylformamide (DMF) and water. The solvent is much more selective for benzene than for n-heptane at 20°C. For two different solvent compositions, calculate interstage flow rates and compositions by the rigorous ISR method for the countercurrent liquid-liquid extraction cascade, which contains five equilibrium stages and is shown schematically in Fig. 15.22. 

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