Toluene sulfuric acid reaction

Mitsubishi Chemical Industries, Ltd. practiced a Henkel II technology starting with toluene to produce benzoic acid. Reaction of benzoic acid with potassium hydroxide resulted in potassium benzoate, which was subjected to a disproportionation reaction to produce dipotassium terephthalate and benzene. Dipotassium terephthalate reacted with sulfuric acid, and the resulting terephthahc acid was recovered by filtration and drying (65,66). Here, dipotassium sulfate was the by-product. 

Two complementai y reviews of this subject are by Shah et al. AIChE Journal, 28, 353-379 [1982]) and Deckwer (in de Lasa, ed.. Chemical Reactor Design andTechnology, Martinus Nijhoff, 1985, pp. 411-461). Useful comments are made by Doraiswamy and Sharma (Heterogeneous Reactions, Wiley, 1984). Charpentier (in Gianetto and Silveston, eds.. Multiphase Chemical Reactors, Hemisphere, 1986, pp. 104—151) emphasizes parameters of trickle bed and stirred tank reactors. Recommendations based on the literature are made for several design parameters namely, bubble diameter and velocity of rise, gas holdup, interfacial area, mass-transfer coefficients k a and /cl but not /cg, axial liquid-phase dispersion coefficient, and heat-transfer coefficient to the wall. The effect of vessel diameter on these parameters is insignificant when D > 0.15 m (0.49 ft), except for the dispersion coefficient. Application of these correlations is to (1) chlorination of toluene in the presence of FeCl,3 catalyst, (2) absorption of SO9 in aqueous potassium carbonate with arsenite catalyst, and (3) reaction of butene with sulfuric acid to butanol. 

Both 2,5-dialkyl-3-furoates and 2,5-dialkyl-3-phosphonofurans can be produced using the Paal-Knorr reaction. Methyl 2,5-diisopropyl-3-furoate (62) is available upon treatment of dione 61 with sulfuric acid. Phosphonodiones 63 can be efficiently converted into 2-substituted-3-diethylphosphono-5-methylfurans 64 by exposure to Amberlyst in refluxing toluene. ... 

Nitration vs side-chain oxidation of toluene in dilute MA was investigated by Namba et al (Ref 69). They found that addition of sulfuric acid accelerated both reactions but nitration more than oxidation. Addition of water to the MA favors oxidation as does an increase in reaction temp... 

A typical chem manufg operation is the production of trinitrotoluene — TNT, the dominant mil expl. It involves the manuf of huge quantities of nitric and sulfuric acids, from sulfur and ammonia, in chem plants exactly similar to those which make nitric and sulfuric acids in the civilian economy. Mixed nitric and sulfuric acid is then combined with liq toluene in a series of reaction kettles... 

In weaker acid systems, other reactions involving the triplet state supervene to the exclusion of dimerization. Photolysis of 85 in 3-3% sulfuric acid, 96-5% acetic acid, and 0-2% water gave as products tri-phenylmethane (93), 9-phenylfluorene (94), 6is-9-phenylfluorenyl peroxide (95) and benzophenone (96). When benzene was present, tetra-phenylmethane (97) was also formed in addition to the other products. When the triphenylmethyl cation is irradiated in 3-3% H2SO4, 80 1% HOAc, 16-4% toluene, and 0-2% H2O, the products observed were... 

Quantitatively transfer the hydrolysis reaction solution to a 50-mL glass culture tube with a screw-cap by rinsing witli 3x5 mL of deionized water followed by 5 mL of 30% (v/v) sulfuric acid and one additional 5 mL of deionized water. Rinse the Teflon culture tube with acetone and transfer to the glass culture tube. Extract the acidic aqueous phase (pH 1) with 3 x 2.5 mL of toluene. Pass each upper toluene phase through approximately 3 g of anhydrous sodium sulfate contained in a 6-mL disposable filtration cartridge into a 10-mL volumetric flask. Adjust the volume of the solution to 10 mL with toluene. Condition a 3-mL diolsilane bonded silica gel SPE cartridge with two column volumes of toluene. Load a 5-mL aliquot of toluene solution and collect the eluate in a 125-mL round-bottom flask. Elute the column with an additional 50 mL of toluene (use the 75-mL reservoirs) and collect the eluate in the same round-bottom flask. Concentrate the toluene extract to approximately 3.0 mL at 40 °C under weak reduced pressure with a rotary evaporator. 

Table 3 shows melting points of a few representative keto acids (72). The reaction of keto acids (66) with phenols (67) is usually carried out in 70-90% sulfuric acid at 50-150°C, or in an aromatic solvent such as benzene, toluene, or chlorobenzene at reflux in the presence... 

Benzyl Alcohols. Benzyl alcohols of nearly all kinds undergo reduction when treated with acid in the presence of organosilicon hydrides. The most obvious exception to this is the behavior of benzyl alcohol itself. It resists reduction by the action of trifluoroacetic acid and triethylsilane, even after extended reaction times.26 Reducing systems consisting of triethylsilane and sulfuric acid/acetic acid or p-toluenesullonic acid/acetic acid mixtures also fail to reduce benzyl alcohol to toluene.134 As previously mentioned, substitution of boron trifluoride for trifluoroacetic acid results in the formation of modest yields of toluene, but only when a very large excess of the silane is used in order to capture the benzyl cation intermediate and suppress Friedel-Crafts oligomerization processes.129,143... 

Nitration of toluene by mixture of nitric and sulfuric acids produces an explosive material known as TNT (trinitrotoluene). The overall reaction can be shown as... 

Acetone (100 mL) was slowly added to quench the excess borane. The reaction mixture was concentrated to 300 mL and toluene (700 mL) was added. The solution was washed with 2% sulfuric acid (350 g) then with 20% NaCl (120 g). The organic phase was concentrated to 300 mL and cooled to 5°C. 

Alkylation of toluene and acetylene in the presence of sulfuric acid is accomplished in the four-stage reactor of the sketch. Retention time in each stage is 10 min, temperature is 41 F and pressure is 50 psig. On the assumption that the liquid always is saturated with acetylene, the reaction is first order with respect to toluene. At the conditions shown, the reaction is estimated 95% complete. Find the specific reaction rate. 

Toluene was nitrated with mixed aqueous nitric-sulfuric acid in a stirred tank at 35 C (Barduhn Kobe, Ind Eng Chem 48 1305, 1956). They found the reaction to occur in the acid phase with the rate equation... 

The above procedure differs from that recorded in the literature, mainly in the use of a fairly large excess of sulfuric acid. This shortens the reaction time from forty hours to about one hour, which is especially convenient in the preparation of the acid on a laboratory scale. Because of the use of this large excess of sulfuric acid, the reaction is apt to be rather violent if the directions given are not carefully followed. The oxidation should be carried out under a hood. Small amounts of nitro-toluene are lost by volatilization, but this loss is not serious, as can be seen from the yield of product obtained. 

The reaction of various A-tosylated a-amino acids (94) with benzene in concentrated sulfuric acid yielded diphenyl derivatives (95)." The mechanism proposed for the reaction (Scheme 9) involves initial protonation of the carboxyl group to give (96), which suffers decarbonylation to the A-tosyliminium salt (97). This reactive electrophile (97) interacts with benzene to give a monophenyl compound (98) which, via a Friedel-Crafts reaction, interacts with another molecule of benzene to yield the diphenyl compound (95)." Toluene and p-xylene reacted analogously to yield diarylated products. 

Esterification Reactions. The use of solid acids provides a practical substitute for homogeneous acid catalysts commonly employed to prepare alkyl esters. The use of homogeneous acid catalysts, such as sulfuric acid, and p-toluene- or methane-sulfonic acids, generally results in sulfur contamination of the final product, which upon combustion yield compounds that are known pollutants. 

Even so, a number of chemical agents, including liquids, chemically attack polymers. Reactions that would ordinarily occur with small molecules also occur in polymers, given the same functional groups and reactive sites. Thus benzene, toluene, etc., are readily sulfonated when exposed to sulfuric acid. Likewise polystyrene (PS) is sulfonated when exposed to liquids and gases containing sulfuric acid ... 

TNT is the abbreviation of the aromatic nitrated aromatic compound 2,4,6-trinitrotoluene. It is a pale-yellow crystalline solid that was first synthesized in 1863 by the German chemist Joseph Wilbrand (1811—1894), but it was not immediately used as an explosive. TNT is made by nitrating toluene using nitric acid, sulfuric acid, and oleum (a mixture of sulfuric acid and S03). Nitration of toluene occurs in stages, with the nitro units added sequentially in a stepwise process as the reaction proceeds. The last nitro unit is accomplished by using oleum (SO, dissolved in sulfuric acid). After nitration, unused acids are recycled, and the product is washed with sodium sulfite and water to remove impurities. 

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