Trifluoroacetic acid → 1-Isopropyl-7-(methylsulfonyl)-1,2,3,4-tetrahydrobenzo[4,5]imidazo[1,2-a]pyrazine

Participants

Reaction Steps

To a solution of tert-butyl 1-isopropyl-7-(methylsulfonyl)-3,4-dihydrobenzo[4,5]imidazo[1,2-a]pyrazine-2(1H)-carboxylate (20.mg, 0.05 mmol) in CH2Cl2 (1 mL) was added TFA (0.3 mL) under N2. The mixture was stirred at rt for 1 h. The mixture was concentrated to afford 1-isopropyl-7-(methylsulfonyl)-1,2,3,4-tetrahydrobenzo[4,5]imidazo[1,2-a]pyrazine (20 mg, TFA salt, 100% yield) as a yellow solid, which was used for the next step without further purification. LC-MS m/z 352.1 [M+H]+.

Provenance & Evidence