Hydrogen Bromide → 3-Bromo-4'-chloro-4-ethylbiphenyl

HRID 43328Notes

Reaction equation

[Cl:1][C:2]1[CH:7]=[CH:6][C:5]([C:8]2[CH:9]=[CH:10][C:11]([CH2:15][CH3:16])=[C:12]([CH:14]=2)N)=[CH:4][CH:3]=1.N([O-])=O.[Na+].[BrH:21]>O>[Cl:1][C:2]1[CH:7]=[CH:6][C:5]([C:8]2[CH:9]=[CH:10][C:11]([CH2:15][CH3:16])=[C:12]([Br:21])[CH:14]=2)=[CH:4][CH:3]=1

Participants

Conditions

Temperature: -5 °C

Procedure

Hydrobromic acid (48% wt. in water, 85 ml) is added dropwise to a suspension of 5-(4-chlorophenyl)-2-ethylaniline (14.3 g, 0.062 mol) in water (57 ml), and the mixture stirred. The mixture is cooled to −5° C. and a solution of sodium nitrite (5.07 g, 0.072 mol) in water (25 ml) is added dropwise, maintaining the temperature at 0-5° C. The reaction mixture is stirred for 1 hour, then added to a pre-cooled solution of cuprous bromide (9 g, 0.062 mol) in hydrobromic acid (48% wt. in water, 64 ml) at 0° C. The reaction mixture is stirred and allowed to warm to room temperature overnight. The mixture is diluted with water, extracted with diethyl ether, and the organic extracts are combined, dried over anhydrous sodium sulfate, filtered and the filtrate concentrated in vacuo. The residue is further purified by column chromatography on silica gel, eluting with 2% ethyl acetate in hexane to give 5-(4-chlorophenyl)-2-ethyl-1-bromobenzene (10 g).

Workup

temperaturemaintaining the temperature at 0-5° C
stirringThe reaction mixture is stirred for 1 hour
stirringThe reaction mixture is stirred
temperatureto warm to room temperature overnight
extractionextracted with diethyl ether
dry with materialdried over anhydrous sodium sulfate
filtrationfiltered
concentrationthe filtrate concentrated in vacuo
customThe residue is further purified by column chromatography on silica gel
washeluting with 2% ethyl acetate in hexane

Sources & evidence

ORD record: ord-5f08c0625a4b481e890c1b41d0d4f17d
Source dataset: uspto-grants-2013_09
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US08536351B2

Reaction notes

Loading…