Hydrochloric Acid → (3S,4R)-3,4-Dimethyl-1-oxo-1,2,3,4-tetrahydro-pyrazino[1,2-a]indole-7-carboxylic acid

Participants

Reaction Conditions

Reaction Steps

To a suspension of ethyl cis-3,4-dimethyl-1-oxo-1,2,3,4-tetrahydropyrazino[1,2-α]indole-7-carboxylate (2.1 g, 7.3 mmol) in ethanol (60 mL) is added 1M NaOH solution (20 mL, 20 mmol). The reaction mixture is heated at 80° C. for 1 h and then cooled to room temperature. The reaction mixture is acidified using concentrated HCl and ethanol is removed under vacuum. The resulting solid is filtered, rinsed with water and dried to afford the title compound (1.8 g, 96%).

Provenance & Evidence