M Bromophenol

Intermediates benzene to nitrobenzene to m bromonitrobenzene to m bromoanihne to m bromophenol Reagents HNO3 H2SO4 Br2 FeBr3 Fe HCl then HO NaN02 H2SO4 H2O then heat in H2O... 

Intermediates benzene to nitrobenzene to i-bromonitrobenzene to i-bromoaniline to m-bromophenol. Reagents HNO3, H2SO4 Br2, FeBr3 Fe, HCl then HO NaN02, H2SO4, H2O, then heat in H2O. 

A three-necked 500mL round-bottom flask was fitted with a reflux condenser, magnetic stir bar, stopper, and gas lnlet/outlet adapters. Under dry nitrogen the flask was charged with m-bromophenol (10.Og, 57.8 mmol), 2-methyl-3-butyn-2-ol (5.0g, 59.4 mmol) and 250 mL of distilled trlethylamlne resulting in a pale yellow solution. The mixture was heated at reflux for 15 min while... 

Brown has reported that poly-1.3-phenylene ether (I) with a molecular weight in the neighborhood of 10,000 can be prepared by heating alkali metal salts of m-bromophenol, in solution, in the presence of copper metal or copper salts. Generally, the reactions were performed between 110° C and 200° C in solvents such as pyridine, nitrobenzene and phenyl ether (9, 10). 

In HF-SbFs solution 4-aIkyl- and 2,6-dialkylphenols and their methyl ethers (anisoles) are converted to the O-protonated forms, which react with Br2 to afford m-bro-mophenol derivatives selectively (Scheme 14.35) [83, 84]. In HF-SbFs o- and p-bro-mophenols isomerize to m-bromophenol by a 1,2-Br shift in fhe protonated forms [85], When NaBr or KBr is used instead of Br2, the meta selectivity is reduced [86]. ElectrophiUc halogenation of arenes can also be performed with Ar SeCl [87]. 

Dimethyl sulfate (38.4 g., 0.30 mole) is added slowly (Caution— toxic substance) with stirring to a solution of 44 g. (0.26 mole) of m-bromophenol (p. 54) in 107 g. of a 10% aqueous solution of sodium hydroxide. Stirring is continued until the reaction mixture is neutral. The organic layer is separated by ether extraction, and the ethereal solution is dried. Distillation gives a colorless oil, b.p. 209-212°/752 mm. This is redistilled and 35 g. (73%) of m-bromoanisole is collected at 210-211°. 

A hot solution of 50 g. (0.29 mole) of m-bromoaniline and 50 ml. of concentrated sulfuric acid in 400 ml. of water is cooled to 10° and diazotized by the addition of 21 g. (0.30 mole) of sodium nitrite at 10°. The solution of the diazonium salt is added (15-30 minutes) in a thin stream to a solution of 100 ml. of concentrated sulfuric acid and 300 ml. of water which is being steam-distilled during the addition at such a rate that, upon completion of the addition of the diazonium salt, approximately 1 1. of distillate has been collected. Steam distillation is continued until another liter of distillate has been collected. The distillate is saturated with sodium chloride and extracted three times with ether. The ether extracts are distilled to give 39 g. (78%) of m-bromophenol boiling at 125-130°/25 mm. 

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