Hydrochloric Acid → 2,6-Dibromotoluene

Temperature

0 °C

A solution of (3,5-dibromo-4-methylphenyl)amine dissolved in water (80 mL) and concentrated HCl (7.5 mL) stirring for 20 min, then the mixture was cooled to 0˜5° C., and a solution of NaNO2 (3.4 g/40 mL H2O) was added. The reaction mixture was stirred for 2 h at 0˜5° C., then the suspension was added to a solution of hypophosphorous acid (50%, 27.9 g), and the mixture was cooled to 0° C. The mixture was stirred at room temperature overnight. Then it was extracted with CH2Cl2 (100 mL×2). The organic layer was washed with brine (30 mL) and dried over Na2SO4. After silica column chomatography, (eluted with petroleum ether), 3.57 g product was obtained, as a colorless liquid. 1H NMR (400 MHz, CDCl3) δ 2.57 (s, 3H), 6.89 (t, J=8.0 Hz, 1H), 7.50 (d, J=8.0 Hz, 2H).

1. temperaturethe mixture was cooled to 0˜5° C.
2. stirringThe mixture was stirred at room temperature overnight
3. extractionThen it was extracted with CH2Cl2 (100 mL×2)
4. washThe organic layer was washed with brine (30 mL)
5. dry with materialdried over Na2SO4
6. washAfter silica column chomatography, (eluted with petroleum ether), 3.57 g product
7. customwas obtained, as a colorless liquid

ORD record

ord-51ad99d9162845638a88fc87fb075080

Source dataset

uspto-grants-2011_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08071588B2