3-Nitro-4-bromoanisole

Nitro-4-aminoanisole (16.8 g., 0.10 mole) [Org. Syntheses, 25, 78 (1945) ] is added to a solution of 30 ml. of concentrated sulfuric acid and 100 ml. of water, and the resulting mixture is cooled to 0-5°. A solution of 7 g. (0.102 mole) of sodium nitrite in 20 ml. of water is added slowly at this temperature, and the mixture is allowed to stand for 2 hours at 0-5°. After filtration to remove a small amount of 3-nitro-4-aminoanisole, the filtrate is added dropwise to a boiling mixture of 100 ml. of water, 6.4 g. of copper sulfate, 15.6 g. of sodium bromide, and 2 g. of copper powder. After another 30-minute boiling, the mixture is cooled and extracted with ether. The ethereal extracts are washed with water, dried over calcium chloride, and distilled. 3-Nitro-4-bromoanisole boils at 153-154°/13 mm. and is obtained in a 75% yield (17.5 g.). 

CvHaBrF, p-Fluorobenzyl bromide,... 166 CrHaBrNOs, 3-Nitro-4-bromoanisole.. 217 CrHeClNOj, 2-Amino-5-chlorobenzoic... 

Bromoanisole. The competition between ortho and ipso attack (83) is also pertinent to the simultaneous nitration and transbromination of 4-bromoani-sole (Perrin and Skimer, 1971). Charge-transfer nitration leads to mixture of 2-nitro-4-bromoanisole and 2,4-dibromoanisole (and 4-nitroanisole), the relative amounts of which are equivalent to those obtained in the electrophilic nitration of 4-bromoanisole. 

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