Reaction #1162894

Reaction equation

N-(1-ethylpropyl)-3,4-dimethyl-benzenamine

N-nitroso-N-(1-ethylpropyl)-2,6-dinitro-3,4-dimethyl-benzenamine

NaNO2

N-(1-ethylpropyl)-3,4-dimethyl-benzenamine

N-nitro-N-(1-ethylpropyl)-3,6-dinitro-3,4-dimethyl-benzenamine

nitric acid

→

N-(1-ethylpropyl)-2,6-dinitro-3,4-dimethyl-benzenamine

Solvents

dichloroethane

water

Conditions

Workup

1. 1
   Othereach 5000 mm in length with an internal diameter of 4 mm, with temperature sensors fitted at the junctions between them
2. 2
   Temperaturecooled thermostated bath
3. 3
   Otherconditions, approximately 6 kg of reaction mass
4. 4
   Otherwas collected in a separator
5. 5
   OtherAfter phase separation of the acid phase from the organic phase
6. 6
   Otherthis latter which--leaving aside the solvent
7. 7
   Washis washed
8. 8
   Otherin the course of the reaction into N-(1-ethylpropyl)-2,6-dinitro-3,4-dimethyl-benzenamine
9. 9
   OtherOnce the solvent is evaporated

Procedure

The dinitration of N-(1-ethylpropyl)-3,4-dimethyl-benzenamine is carried out in a pilot plant in a tubular reactor having a static mixer; the tubular reactor is constituted by a coil in three joined sections, each 5000 mm in length with an internal diameter of 4 mm, with temperature sensors fitted at the junctions between them. The Kenics Static Mixer is a 190 mm long tubular body inserted between the second and third sections. The reactor is immersed in a water-cooled thermostated bath. 67% nitric acid supplemented with 5000 ppm by weight of NaNO2 is fed to the reactor at a rate of 15 l/h at the same time as a solution of 39% by weight N-(1-ethylpropyl)-3,4-dimethyl-benzenamine in dichloroethane; this solution is fed at a rate of 21 l/h. After a period of 15 minutes, during which time the system reaches operating conditions, approximately 6 kg of reaction mass was collected in a separator. After phase separation of the acid phase from the organic phase, this latter which--leaving aside the solvent--is composed of 95% by weight dinitration products and contains 6.8% by weight N-nitroso-N-(1-ethylpropyl)-2,6-dinitro-3,4-dimethyl-benzenamine and 54 ppm p/p N-nitro-N-(1-ethylpropyl)-3,6-dinitro-3,4-dimethyl-benzenamine, is washed and subjected to denitrosation by treatment with aqueous hydrobromic acid and sulphamic acid to transform its N-nitroso derivative co-produced in the course of the reaction into N-(1-ethylpropyl)-2,6-dinitro-3,4-dimethyl-benzenamine. Once the solvent is evaporated, 1.78 kg of crude N-(1-ethylpropyl)-2,6-dinitro-3,4-dimethyl-benzenamine were obtained with a titre of 94.2%.

Source