Nitration bromotoluene

Bromobenzaldehyde has been prepared by the oxidation of -bromotoluene with chromyl chloride/ by saponification of the acetal from />-bromophenylmagnesium bromide and orthoformic ester/ by the oxidation of ethyl -bromobenzyl ether with nitric acid/ by the oxidation of /j-bromobenzyl bromide with lead nitrate/ and by the hydrolysis of i-bromobenzal bromide in the presence of calcium carbonate. ... 

Addition of ether to a nitration mixture (2-bromotoluene and cone, nitric acid) diluted with an equal volume of water in a separating funnel led to a low order explosion. This was attributed to oxidation of the ether (possibly containing alcohol) by the... 

Nitration of p-BrC HjCH, would have given about a 50-50 mixture of two products 2-nitro-4-bromotoluene would be unwanted. When oxidation precedes nitration, an excellent yield of the desired product is obtained. 

Trinitrobromotoluene, (02N)3(Br).C6H.CH3 mw 306.04, N 13.73% Only one isomer is described in-the literature 2,4,6-Trinitro-3-bromotoluene, col ndls(from ale), mp 143 4°, sol in ale, insol in liqroin was first prepd by nitrating 2,4-dinitro -5 bromotoluene and later by diazotizing 2,6 -dinitro-3-bromo-4 aminotoluene(Ref 1). Qvist et al(Ref 2) prepd this compd by nitrating the 5-bromo deriv of o-cymene(isopropyltoluene) and also by nitrating 2,4 dinitro-5-bromotoluene(Ref 3). The trinitrobromotoluene is definitely an expl compd although no investigator has reported its expl props... 

Five per cent, of selenium in excess of that required by the foregoing equation is used. The mixture is heated for twelve hours at 220° C., then for a short time at 235° to 240° C. By this method the selenide is obtained in rectangular plates, M.pt. 61° to 62° C., B.pt. 186° C. at 16 mm. When aluminium and selenium bromides react with toluene, the chief product is o-bromotoluene, but a small amount of di-o-tolyl selenide also results, B.pt. 174° to 180° C. at 13 mm.8 It yields a dibromide on treatment with bromine and a nitrate with nitric acid. 

Taking that into account, Holleman [55] calculated which isomers were formed when nitrating bromotoluenes. These calculations were based on the following experimental data of his own ... 

Since toluene, when nitrated, yields the ortho- and met a- isomers in the quantities shown in diagram IV, and bromobenzene in those shown in diagram V, for p- bromotoluene the quantities can be calculated. They are shown in diagram VI. 

In addition to the reaction schemes described earlier, there are many other types of systems that are quite common. In one of these, a single reactant may be converted into several different products simultaneously. There are numerous examples of such reactions in organic chemistry. For example, the reaction of toluene with bromine in the presence of iron at 25°C produces 65% p-bromotoluene and 35% o—bromotoluene. Similarly, the nitration of toluene imder different conditions can lead to different amounts of o—nitrotoluene and p-nitrotoluene, but a mixture of these products is obtained in any event. Tailoring the conditions of a reaction to obtain the most favorable distribution of products is a common practice in synthetic chemistry. We will now illustrate the mathematical analysis of the kinetics of such reactions. 

Potassium 2-nitrobenzoate (22.6 g, 110 mmol), (l,10-phenanthroline)bis(triphenyl-phosphine)copper(I) nitrate (1.25 g, 1.50 mmol), and palladium acetylacetonate were diluted in deoxygenated, anhydrous mesitylene (150 mL), and 2-bromotoluene (12.3 mL, 100 mmol) was added under an atmosphere of nitrogen. The reaction mixture was stirred for 16 h at 150 °C internal temperature. After cooling to ambient temperature, the reaction mixture was filtered through a pad of Celite and the filter cake was rinsed with ethyl... 

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