N-bromobutanimide → alpha-Bromo-5-[3,6-dihydro-3-methyl-2,6-dioxo-4-(trifluoromethyl)-1(2H)-pyrimidyl]-1,2-benzisothiazole-3-acetonitrile

Participants

Reaction Steps

To a solution of 5-[3,6-dihydro-3-methyl-2,6-dioxo-4-(trifluoromethyl)-1(2H)-pyrimidinyl]-1,2-benzisothiazole-3-acetonitrile (0.500 g, 0.00140 mol) in 1,2-dichloroethane is added N-bromosuccinimide (0.250 g, 0.00140 mol). The resultant mixture is irradiated with a UV lamp and stirred at reflux six hours. Additional N-bromosuccinimide (0.250 g, 0.00140 mol) is added and the resultant mixture is stirred 1.5 hours at reflux under a UV lamp. The mixture is cooled to room temperature and concentrated in vacuo. The resultant residue is taken up in methylene chloride, washed with water, treated with charcoal, dried over anhydrous magnesium sulfate, filtered, and concentrated in vacuo to give the title product as a red glass (0.350 g, 56.2%, mp 185-187° C.) which is identified by IR and NMR spectral analyses.

Provenance & Evidence