Hydrochloric Acid → 4-Bromo-3-chlorobenzenethiol

Temperature

0 °C

4-Bromo-3-chloro-benzenesulfonyl chloride (3.78 g, 13.0 mmol) was dissolved in dichloromethane (40 ml) and DMF (1.0 ml) was added. The mixture was cooled to 0° C. under argon and triphenylphosphine (10.26 g, 39.0 mmol) was added slowly, then the mixture was allowed to return to room temperature with stirring over 16 h. Hydrochloric acid (1 M, 75 ml) was added and the layers were separated. The organic layer was concentrated and the residue suspended in 1 M aqueous sodium hydroxide (75 ml) and filtered. The filtrate was extracted with Et2O (×2), then neutralised (1 M HCl, 75 ml). The mixture was then extracted (Et2O×3) and the combined organic layers were dried (Na2SO4) and concentrated to afford the title compound as a colourless oil (0.94 g, 32%). 1H NMR (CDCl3 400 MHz) 3.49 (1H, s), 7.02 (1H, dd, J=8.35, 2.24 Hz), 7.38 (1H, d, J=2.18 Hz), 7.45 (1H, d, J=8.35 Hz).

1. customto return to room temperature
2. customthe layers were separated
3. concentrationThe organic layer was concentrated
4. filtrationfiltered
5. extractionThe filtrate was extracted with Et2O (×2)
6. extractionThe mixture was then extracted (Et2O×3)
7. dry with materialthe combined organic layers were dried (Na2SO4)
8. concentrationconcentrated

ORD record

ord-72b293c707b64564a1ca018a73c73c73

Source dataset

uspto-grants-2010_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07855216B2