Methyl nitrate → 4-Bromo-2,6-dimethyl-N-nitroaniline

Temperature

-10 °C

To a cooled (-60° C.) solution of 4-bromo-2,6-di-methylaniline (0.037 mole, 7.4 g) dissolved in anhydrous ether (100 ml) under nitrogen with stirring is added dropwise, phenyl lithium (21.5 ml, 0.040 mole). The solution is stirred for 1.5 hours at -60° C. The solution is allowed to warm to -10° C., then it is cooled to -60° C. The nitrogen flow is stopped while methyl nitrate (0.044 mole, 3.5 g) in anhydrous ether (25 ml) is added dropwise. The solution is stirred for 0.5 hour at -60° C., then it is allowed to warm to room temperature. The solution is stirred for 1.6 hours; the ether layer is evaporated. The solid is dissolved in water (250 ml), then is extracted with ether (2×100 ml). The cold water layer is acidified with 5% HCl. The precipitated product is filtered, washed with water, and dried in vacuo. Recrystallization from hot hexane yields 2.5 g of the desired product melting at 129°-131° C.

1. additionis added dropwise
2. stirringThe solution is stirred for 1.5 hours at -60° C
3. temperatureit is cooled to -60° C
4. additionis added dropwise
5. stirringThe solution is stirred for 0.5 hour at -60° C.
6. temperatureto warm to room temperature
7. stirringThe solution is stirred for 1.6 hours
8. customthe ether layer is evaporated
9. dissolutionThe solid is dissolved in water (250 ml)
10. extractionis extracted with ether (2×100 ml)
11. filtrationThe precipitated product is filtered
12. washwashed with water
13. customdried in vacuo
14. customRecrystallization from hot hexane

ORD record

ord-7c0325f366d14c15b34af987dd71e9f4

Source dataset

uspto-grants-1987_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04643755