2-Bromo-m-xylene synthesis

10synthesis methods

Product Name:2-Bromo-m-xylene
CAS Number:576-22-7
Molecular formula:C8H9Br
Molecular Weight:185.06

87-62-7
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$10.00/5 g

576-22-7
320 suppliers
$10.00/1g

Yield:576-22-7 42%

Reaction Conditions:

Stage #1:2,6-dimethylaniline with hydrogen bromide;sodium nitrite in ethanol;water at 0; for 0.25 h;
Stage #2: with copper(I) bromide in ethanol;water at 0 - 95; for 0.333333 h;

Steps:

2-Bromo-1,3-dimethylbenzene (S4a)
To a solution of 2,6-xilidine (S3) (1.0 mL, 8.12 mmol, 1 equiv) in EtOH (8.0 mL) and 48% aqueous HBr(4.0 mL) was added a solution of NaNO2 (728 mg, 10.6 mmol, 1.3 equiv) in water (1.0 mL) dropwise at 0 °C, and the mixture was stirred at the same temperature for 15 min. To the mixture was added a solution of CuBr (699 mg, 4.87 mmol, 0.60 equiv) in 48% aqueous HBr (4.0 mL) dropwise at 0 °C. After being stirred at 95 °C for 20 min, the reaction mixture was cooled to room temperature and diluted with EtOAc and water. The organic layer was separated, and the aqueous layer was extracted with EtOAc twice. The combined organic layers were washed with saturated aqueous NaHCO3 and brine, dried over MgSO4 and filtered. The filtrate was concentrated in vacuo, and the resulting residue was purified by flash column chromatography on silica gel (eluted with hexane) to afford the bromide S4a (630 mg, 3.44 mmol, 42%) as an orange oil.

References:

Ohsawa, Kosuke;Yoshida, Masahito;Izumikawa, Miho;Takagi, Motoki;Shin-ya, Kazuo;Goshima, Naoki;Hirokawa, Takatsugu;Natsume, Tohru;Doi, Takayuki [Bioorganic and Medicinal Chemistry,2018,vol. 26,# 23-24,p. 6023 - 6034] Location in patent:supporting information

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