Y>-Nitrotoluene

Processes. Toluene is nitrated ia two stages. Mononitration occurs ia mixed acid, 30% HNO and 55% H2SO4, at 30—70°C ia a series of continuous stirred-tank reactors. Heat is Hberated and must be removed. The isomer distribution is approximately 58% o-nitrotoluene 38% -nitrotoluene, and 4% y -nitrotoluene (Fig. 1). 

One way to assess the relative stabilities of these var ious intermediates is to examine electron delocalization in them using a resonance description. The cyclohexadienyl cations leading to o- and p-nitrotoluene have tertiar y car bocation character. Each has a resonance form in which the positive charge resides on the carbon that bear s the methyl group. 

Eodisch, R., Honicke, D., Xu, Y., Platzer, B., Liquid phase hydrogenation of p-nitrotoluene in microchannel reactors, in Matlosz, M., Ehrfeld, W., Baselt,... 

In pyridine derivatives, a- and y-picolines readily lose a proton from the methyl group. It is easy to fmd parallel reactivity in the picolines and the nitrotoluenes N=CHN02. Further development of the reactivity patterns includes a methano-lytic study of several trichloromethylpyridines [29],... 

Abstract—The equilibrium diagrams of the binary systems of sulphuric add with nitromethane and with o-y m- and p-nitrotoluene have been investigated. It has been shown that addition compounds of the type 1 1 are formed in these systems, analogous to the compound sulphuric acid-nitrobenzene (Chebbuuez Helv, Chim, Acta 1923 6 281 and Masson J. Chem. Soc. 1931 3201)t The formation of these addition compounds is due to hydrogen bonding between the components, rather than to proton transfer. Their stability in the crystalline phase seems to be contradictory to the known basicities of mononitrocompounds (Gillespie and Solomons J. Chem. Soc, 1957 1796), because of the effect of temperature on the equilibria in the liquid phase. 

This process is used in the sulphonation of y-nitrochlorobenzene, p-nitrotoluene, o-nitrochlorobenzene, chlorobenzenes, etc. 

One of the most common photochemical reaction pathways of carbonyl compounds is the formation of a diradicaloid excited state which is able to abstract a hydrogen atom at the y (or, more rarely, e) position, followed by either fragmentation or recombination. This process, which is known as the Norrish type II reaction, has a parallel in the photochemistry of nitro groups the intramolecular hydrogen abstraction of excited ortho-nitrotoluene is actually one of the very early synthetic photochemical transformations [9]. It has been exploited in a family of photolabile protecting groups, most prominent among which are derivatives of ortho-nitrobcnzyl alcohol, as introduced in 1966 by Barltrop et al. (Scheme 13.1) [10, 11],... 

All isomers are formed by nitration of m- nitrotoluene. Hepp [35] isolated the p- and y- isomers from the product of a severe nitration of m- nitrotoluene. Their structures have been determined by Will [37],... 

The Reissert synthesis of indoles has found much success with o-nitrotoluenes, but has been tried for the s5nithesis of azaindoles in only a few cases. Herz and Murty first reported unsuccessful attempts at base-catalyzed condensation of ethyl oxalate with 4-nitro-3-picoline and its Y-oxide (45). No conditions were reported. Later,... 

Xu Y. and Herman J. A., Detection of nitrotoluene isomers by ion cyclotron resonance mass spectrometry using ion/molecule reactions with NO+ as reagent. Rapid. Commun. Mass. Spectrom., 6(7), 425-428, 1992. 

A soln. of o-nitrotoluene in methanol pyrolyzed at 600° with a contact time of 11 sec. methyl anthranilate. Y 48%. - A wide variety of subst. anthranilic esters difficult to prepare otherwise can be obtained by this method. F. e. s. E. K. Fields and S. Meyerson, Tetrah. Let. 1968, 1201. 

The enaminate anions produced by deprotonating a- and y-alkylpyridines can participate in a wide range of reactions,being closely analogous to eno-late anions. Similar side-chain carbanion formation is seen in ortho- but not ffieta-nitrotoluene. 

R. Fddisch, D. Honicke, Y. Xu, B. Platzer, Liquid phase hydrogenation of p-nitrotoluene in microchannel reactor, in Microreaction Technology - IMRET 5 Proceedings 5th International Conference on Microreaction Technology, 2001. 

Bromo-4-nitrotoluene heated 3-4 hrs. at 130° with dil. HNO3 and 1 drop of Hg as catalyst in a sealed tube 2-bromo-4-nitrobenzoic acid. Y 76%.— By addition of Hg, the reaction can be performed at lower temp, and in shorter time. K. Friedrich and H. Oster, B. 94, 834 (1961). 

Umansky et al. [106] showed that the intensive factor (acid site strengths) dominates over the extensive factor (concentration of the active sites) in controlling acid-base properties and the catalytic activity. The conclusion was reached by comparing the activity to convert isobutane of silica-aluminas, Y, ZSM-5, MOR, and b-zeolites, as well as sulfated zirconia and SbFs-promoted silica-alumina to the acidity expressed as Ho values of the strongest acid sites, which were determined from the spectral shift of adsorbed 4-nitrotoluene and 4-nitrofluorobenzene. 

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