1.2.3- Trifluorobenzene

Question. List the symmetry elements of each of the following molecules (a) 1,2,3-trifluorobenzene, (b) 1,2,4-trifluorobenzene, (c) 1,3,5-trifluorobenzene, (d) 1,2,4,5-tetrafluoro-benzene, (e) hexafluorobenzene, (f) l,4-dibromo-2,5-difluorobenzene. 

A second fluorine substituent shields in the ortho- and especially in the para-position, but one in the meta-position deshields, with 1,3-5-trifluorobenzene having the most deshielded fluorines in a polyfluoro-aromatic system (Scheme 3.58). On the other hand, hexafluorobenzene has highly shielded fluorines. The fluorine spectra of these multifluoro-benzenes are second order in nature and their appearance is thus not generally predicable on the basis of first-order logic. 

Harper and Lynden-Bell [40] studied 1 1 mixtures of benzene, 1,3,5-trifluorobenzene, and hexafluorobenzene in [QCilm][PFg]. For benzene it was found fhaf cations are concentrated above and below the plane of... 

Nitric acid, Sulfuric acid, Phloroglucinol, Hydrochloric acid Sodium chlorate. Copper sulfate. Ammonium hydroxide. Alcohol Sodium chlorate. Copper sulfate. Ammonium hydroxide. Alcohol Sulfuric acid. Potassium nitrate, 1,3,5-Trifluorobenzene, Methylene chloride. Hexane, Charcoal, Sodium sulfate, 2-Amino-2-methylpropanone, Potassium hydrogen carbonate, 1,2-Dichloroethane, Trifluoroacetic acid. Urea, Dimethylformamide Nitric acid. Urine... 

Potassium nitrate, Sulfuric acid, 1,3,5-Trifluorobenzene, Methylene chloride, Hexane, Tert-butylamine, Trifluoroacetic acid, 1,2-Dichloroethane, 3-Amino-1,2,4-traizole, Glacial acetic acid, Sodium nitrite, Urea, Ethyl acetate, Dimethylformamide, Diethyl ether, Sodium sulfate, Methanol Ethanolamine, Diethyl ether, Ethyl chlorocarbonate, Sodium hydroxide, Magnesium sulfate, Nitric acid, Anhydrous ammonia... 

This has been demonstrated in a comparative study479 using nitronium salts in the nitration of deactivated polyfluoronitrobenzenes performed in dichloromethane and sulfolane, as well as triflic acid. When 2,4-difluoronitrobenzene, 2,3,4-tri-fluoronitrobenzene, and 1,3,5-trifluorobenzene were reacted with N02+BF4 in... 

The dipole moment correlation of trifluorobenzenes (dataset consisting of 1,2,3-trifluorobenzene, 1,2,4-tiifluorobenzene, and 1,3,5-trifluorobenzene) is better than that for dichlorobenzenes of the halide class ... 

Pentane, benzene, pyridine, 1-chlorobutane, 1-bromobutane, 1-butanol, 1,3-dichloropropane, fluorobenzene, /7-butylamine, phenol, 1,2,3,5-tetrafluorobenzene, acetone Mesitylene Nitrobenzene 1,3,5 -Trifluorobenzene Tolune (low temp.)... 

Chemical Name 1,3,5-trifluorobenzene CAS Registry No 372-38-3 Molecular Formula C6H3F3 Molecular Weight 132.083 Melting Point (°C) ... 

TABLE 6.1.3.6.1 Reported vapor pressures of 1,3,5-trifluorobenzene at various temperatures Findlay 1969 ... 

FIGURE 6.1.3.6.1 Logarithm of vapor pressure versus reciprocal temperature for 1,3,5-trifluorobenzene. 

There is a long history of using Rayleigh-wing and related spectroscopies to study orientational dynamics of symmetric-top liquids (31). Liquids that have been studied include carbon disulfide (11,15,26,36-43), acetonitrile (26,44-47), benzene [(11,32,45,48-52), hexafluorobenzene (32,48,52), 1,3,5-trifluorobenzene (52)], mesitylene (32,44,50,52), chloroform (45,48,53), and methyl iodide (34,45,54,55). 

Since the development of the Fourier-transform deconvolution procedure for OHD-RIKES data by McMorrow and Lotshaw (22), the intermolecular dynamics of a wide range of liquids have been studied with this technique (26,52,65-85). Figure 13 illustrates representative OKE reduced spectral densities we have recorded in symmetric-top liquids, including acetonitrile, benzene, benzene-d6, carbon disulfide, chloroform, hexafluorobenzene, mesitylene, and 1,3,5-trifluorobenzene. Although there are conspicuous differences among these spectra, they are all broad and relatively featureless. Indeed, with rare exceptions the reduced spectral densities of simple liquids are devoid of sharp features, which makes it difficult to find an unambiguous interpretation of these spectra. 

Figure 13 Room-temperature reduced spectral densities for (a) acetonitrile, (b) benzene, (c) benzene-d6, (d) carbon disulfide, (e) chloroform, (f) hexafluoro-benzene, (g) mesitylene, and (h) 1,3,5-trifluorobenzene. 

Place 2400 milliliters of 30% fuming sulfuric acid into a 6-liter 3-neck flask equipped with a stirrer and thermometer, and then cool the acid to 0 Celsius by means of an ice bath. Then, while maintaining the acid at 0 Celsius and stirring, slowly add 560 grams of potassium nitrate in small portions over a 2-hour period. After the addition of the potassium nitrate, remove the ice bath, and then place the reaction mixture into a hot water bath at 50 Celsius. Then slowly add 112 grams of 1,3,5-trifluorobenzene over a period of 2 hours while maintaining the temperature of the reaction mixture at 50 Celsius and stirring. 

Binary mixtures of benzene, 1,3,5-trifluorobenzene and hexafluorobenzene with ( jiTiim 11 PI G1 were modeled with MD simulations [122], The local ordering of the ions at an aromatic molecule was found to depend on the quadrupole moment of the aromatic species and to remain qualitatively the same on varying the mole fraction of the aromatic species. Interaction energies showed the most significant interactions to be between the aromatic molecule and the ions located at its equator [122],... 

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