Dichloromethane → 6-{6-bromo-5-[(dimethyl-lambda~4~-sulfanylidene)amino]-3-phenyl-2-pyrazinyl}-2-isopropyl-3 (2H)-pyridazinone

Participants

Reaction Conditions

Reaction Steps

To a solution of DMSO (0.75 ml) in CH2Cl2 (5 ml) was added trifluoromethanesulfonic anhydride (1.5 ml) dropwise at <−75° C. under nitrogen. A suspension of 6-(5-amino-6-bromo-3-phenyl-2-pyrazinyl)-2-isopropyl-3(2H)-pyridazinone (3.00 g) in a mixture of DMSO (5 ml) and CH2Cl2 (6 ml) was added and stirred at −65° C. for 2 hours and at −55° C. for one hour. The reaction mixture was quenched with 1N aq. NaOH (20 ml) and stirred at 15° C. for 10 minutes. An organic layer was collected, dried over MgSO4 and concentrated under reduced pressure to give a solid. The solid was suspended in acetone and collected by filtration to give 6-{6-bromo-5-[(dimethyl-lambda˜4˜-sulfanylidene)amino]-3-phenyl-2-pyrazinyl}-2-isopropyl-3(2H)-pyridazinone (3.16 g).

Provenance & Evidence