Trifluoroacetic acid → 1-(4-chlorobutyl)-2-propyl-6,7,8,9-tetrahydro-2H-pyrazolo[3,4-c]quinolin-4-amine

Participants

Reaction Steps

A mixture of 1-(4-chlorobutyl)-2-propyl-2H-pyrazolo[3,4-c]quinolin-4-amine (19.45 g, 61.39 mmol), prepared as described in Example 46, platinum oxide (10.00 g) and trifluoroacetic acid (200 mL) was placed under hydrogen pressure (50 psi, 3.4×105 Pa) for 2 days. The reaction mixture was filtered through CELITE filter aid. The filtrate was concentrated under reduced pressure to provide a dark oil. The oil was chilled in an ice bath, ice was added, and the mixture was made basic (pH 14) by the addition of 1 N potassium hydroxide. The resulting solid was isolated by filtration and then dissolved in dichloromethane. The solution was washed sequentially with 1 N potassium hydroxide, water, and brine, dried over magnesium sulfate, filtered, and concentrated under reduced pressure. The residue was dried under vacuum for 2 days to provide 18.0 g of 1-(4-chlorobutyl)-2-propyl-6,7,8,9-tetrahydro-2H-pyrazolo[3,4-c]quinolin-4-amine as an oil.

Provenance & Evidence