Pyridine → trifluoromethanesulfonic acid 1-acetyl-1H-indazol-5-yl ester

Participants

Reaction Conditions

Reaction Steps

112 μl (1.2 eq; 0.667 mmol) of trifluoromethanesulfonic anhydride and 337 μl (17.5 eq; 49.557 mmol) of pyridine, under an argon atmosphere, are added dropwise to a solution of 98 mg (1 eq; 0.556 mmol) of 1-(5-hydroxyindazol-1-yl)ethanone in 10 ml of dichloromethane on amylene, pre-cooled to 0° C. The medium is stirred and kept at 0° C. overnight under an argon atmosphere. 112 μl of trifluoromethanesulfonic anhydride and 337 μl of pyridine are added to the medium, which is stirred for 2 hours at 0° C. 112 μl of trifluoromethanesulfonic anhydride and 337 μl of pyridine are then added, and the medium is then stirred for 3 hours at 0° C. The reaction mixture is washed with 10 ml of water. The aqueous phase is treated with 2 times 10 ml of dichloromethane. The organic phase is dried over magnesium sulfate and then filtered and the solvent is evaporated off under reduced pressure in a rotary evaporator to obtain 168.9 mg of trifluoromethanesulfonic acid 1-acetyl-1H-indazol-5-yl ester are obtained.

Provenance & Evidence