Toluene, m-Nitro

Three products are possible from nitration of toluene o mtrotoluene m nitro toluene and p mtrotoluene All are formed but not m equal amounts Together the ortho and para substituted isomers make up 97% of the product mixture the meta only 3%... 

XfjT Conversion m-nitro toluene Conversion bromine Selectivity benzyl bromide Selectivity benzal bromide Selectivity side product... 

Fig. 6 High p,T operation for the radical side-chain bromination of m-nitro toluene in a micro-mixer-reactor setup. The large increase in operational temperature increases conversion at good selectivities, which tend to decline slightly with temperature. The two-fold substituted product, m-nitro toluene benzal bromide, is formed in larger amounts at temperatures above 200°C (IMM, unpublished results)...

Beilstein and Kuhlberg nitrated the m-nitro-toluene in 1873 and obtained the 3,4-isomer. 

Nitro-4-amino toluene m-Nitrotoluene (62-72%, pure) H3PO2 gives 75-80% of pure m-nitro toluene. 34... 

N itro-4-aminotoluene Unsuccessful H3PO2 gives 76-80% of m-nitro toluene. With ethanol the yield is 62-72%. 106... 

The general procedure is quoted in Expt 6.80 (cognate preparations) with reference to the preparation of m-nitro toluene and 2,5-dichloroaniline. 

Reduction of o- and / -nitrobenzyl halides at mercury or platinum gives mainly the bibenzyl derivative, with nitrotoluene as a minor product [121-126]. However, m-nitro-toluene is the predominant product of the electrolysis of / -nitrobenzyl halides [123]. 

Some efforts have been made to reduce the proportion of undesirable m-nitrotoluene. A general rule is that the lower the temperature of nitration the smaller the proportion of meta isomer (Vol. I, p. 273). Also the use of nitric acid acetic anhydride mixture at 0 C can assure a lower proportion of m-nitro toluene, for example to reduce it to 1.6% [22]. This is in agreement w ith former findings (Vol, I, p. 274). 

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