Reaction #10304

Reaction equation

N-bromosuccinimide

benzoyl peroxide

CCl4

6-fluoro-3-methyl-1,2-benzisothiazole

→

DCM isohexane

title compound

Yield 51.0%

3-Bromomethyl-6-fluoro-1,2-benzisothiazole

Yield 51.0%

Conditions

Workup

1. 1
   Otherprepared by the method of D
2. 2
   Temperatureat reflux under nitrogen for 6 h
3. 3
   Temperatureto cool
4. 4
   Filtrationfiltered under suction
5. 5
   ConcentrationThe filtrate was concentrated
6. 6
   Otherthe residue purified by flash silica chromatography
7. 7
   Washeluting with 1:2

Procedure

A mixture of 6-fluoro-3-methyl-1,2-benzisothiazole [prepared by the method of D. M. Fink and J. T. Strupczewski, Tetrahedron Lett., 1993, 34, 6525] (761 mg, 4.55 mmol), N-bromosuccinimide (0.89 g, 5.0 mmol) and benzoyl peroxide (102 mg (70% (w/w)), 0.29 mmol) in CCl4 (25 mL) was heated at reflux under nitrogen for 6 h. The mixture was allowed to cool and filtered under suction. The filtrate was concentrated and the residue purified by flash silica chromatography, eluting with 1:2 then 1:1 DCM/isohexane to give the title compound as a white solid (569 mg, 51%). 1H NMR (500 MHz, CDCl3) δ 4.82 (3H, s), 7.25 (1H, dt, J=8.8 and 2.2 Hz), 7.60 (1H, dd, J=8.1 and 2.2 Hz), 8.07–8.10 (1H, m). (471 MHz, CDCl3)δF −111.9.

Source