tert.butyl 2-acetylthiomethyl-hexahydro-3-oxo-1H-pyrazolo[1,2-a]pyridazine-5-carboxylate → 2-acetylthiomethyl-hexahydro-3-oxo-1H-pyrazolo[1,2-a]pyridazine-5-carboxylic acid

Participants

Reaction Steps

1.69 of tert.butyl 2-acetylthiomethyl-hexahydro-3-oxo-1H-pyrazolo[1,2-a]pyridazine-5-carboxylate (diastereomer A) were treated with 10 ml of trifluoroacetic acid at room temperature for 2 hours. The solution was evaporated and the residue was re-evaporated with toluene several times. The residue was then crystallized from acetone to give 1.1 g of 2-acetylthiomethyl-hexahydro-3-oxo-1H-pyrazolo[1,2-a]-pyridazine-5-carboxylic acid having a melting point of 166°-168° C. (decomposition).

Provenance & Evidence