Dimethyl Sulfoxide → Dimethyl sulfide ditriflate

Participants

Reaction Conditions

Reaction Steps

In carrying out the first step of the conversion the selected amino pyrazine of formula III, the reagent is prepared by mixing dimethylsulfoxide in methylene chloride and cooled to -78° C. To the cooled solution is added trifluoromethane sulfonic anhydride in a ratio of approximately 3 moles dimethylsulfoxide to 2 moles of anhydride to produce dimethyl sulfide ditriflate of the formula ##STR8## Then, there is added to the cooled solution of VI the selected amino pyrazine of formula III while maintaining the temperature of the reaction mixture at -78° C. to produce the sulfilimine of formula IV. The resulting suspension is made alkaline with aqueous sodium bicarbonate or sodium hydroxide. Additional methylene chloride is added and the product extracted into the methylene chloride phase which is separated and evaporated to remove the volatile organic solvent leaving the sulfilimine IV as a residue.

Provenance & Evidence