Hydrogen Bromide → 1-Bromomethylthio-4-chlorobenzene

To a slurry of paraformaldehyde (36.24 g, 1.21 mol, 1.58 equiv) in toluene (243 ml) at 22° is added aqueous hydrobromic acid (48.5 wt %, 652 ml, 5.86 mol, 7.68 equiv) with an endotherm to 18°. The resultant biphasic solution is warmed to 40° and a solution of 4-chlorothiophenol (VII, 138.81 g, 0.960 mol, 1.26 equiv) in toluene (116 ml) is added over ½ hour while maintaining 40-43° and rinsed in with toluene (50 ml). The mixture is then warmed to 50° and stirred 1 hour. The mixture is cooled to 10°, the phases separated, and the aqueous washed with toluene (250 ml). The combined organics are treated with ice water (500 ml), hexanes (350 ml) and the phases separated. The aqueous phase is then washed with toluene (200 ml) and the combined organic phases are dried over magnesium sulfate and concentrated to give crude bromomethylthio-4-chlorobenzene (268.01 g), NMR 7.43, 7.34, 4.79 δ; CMR 134.37, 132.05, 131.78, 129.46, 37.32 δ; HRMS (EI+) calculated for C7H6BrClS=235.9063, found =235.9063.

1. temperatureThe resultant biphasic solution is warmed to 40°
2. temperaturewhile maintaining 40-43°
3. washrinsed in with toluene (50 ml)
4. temperatureThe mixture is then warmed to 50°
5. temperatureThe mixture is cooled to 10°
6. customthe phases separated
7. washthe aqueous washed with toluene (250 ml)
8. additionThe combined organics are treated with ice water (500 ml), hexanes (350 ml)
9. customthe phases separated
10. washThe aqueous phase is then washed with toluene (200 ml)
11. dry with materialthe combined organic phases are dried over magnesium sulfate
12. concentrationconcentrated

ORD record

ord-51bb476e58384c06b7f29ee4d78f3e48

Source dataset

uspto-grants-2001_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06265604B1