反应详情

A solution of 2.46 g of 2-chloro-5-(o-chloro-p-trifluoromethyl-phenoxy)-benzoic acid in 20 ml of methylene chloride is added dropwise at room temperature while stirring to a solution of 1.3 g of dicyclohexylcarbodiimide and 0.6 g of dimethyl sulphoximine in 5 ml of methylene chloride, a slight exothermic reaction occurring. After a reaction time of 15 minutes the solvent is removed by evaporation under reduced pressure and the residue is purified by chromatography on silica gel with n-hexane/ethyl acetate (9:1). The white crystalline product is then recrystallized from methylene chloride/n-hexane. There is obtained N-[2-chloro-5-(o-chloro-p-trifluoromethyl-phenoxy)-benzoyl]-S,S-dimethyl-sulphoximine, m.p. 128°-131° C.; mass spectrum: m/e 425/427; 1H-NMR (CDCl3): 7.8-6.9 (m,6H), 3.4 (s,6H).

1. customa slight exothermic reaction
2. customAfter a reaction time of 15 minutes the solvent is removed by evaporation under reduced pressure
3. customthe residue is purified by chromatography on silica gel with n-hexane/ethyl acetate (9:1)
4. customThe white crystalline product is then recrystallized from methylene chloride/n-hexane