Trifluoroacetic acid → 2-butyl-6,7,8,9-tetrahydro-1-(2-methylpropyl)-1H-imidazo[4,5-c][1,8]naphthyridin-4-amine hemihydrate

Participants

Reaction Steps

A catalytic amount of platinum oxide was added to a solution of 2-butyl-1-(2-methylpropyl)-1H-imidazo[4,5-c][1,8]naphthyridin-4-amine (2.0 g, 6.2 mmole) in trifluoroacetic acid (30 mL). The reaction mixture was reduced on a Parr apparatus under 50 psi (3.5 Kg/cm2) hydrogen pressure. The reaction mixture was filtered to remove the catalyst. The filtrate was concentrated under vacuum. The residue was combined with water, sodium bicarbonate and 10% sodium hydroxide. An oil was recovered and purified using reverse phase high performance liquid chromatography eluting with 30:70 buffer (7.68 g potassium phosphate, monobasic; 1.69 g of sodium hydroxide, 1 μL of water):methanol to provide 2-butyl-6,7,8,9-tetrahydro-1-(2-methylpropyl)-1H-imidazo[4,5-c][1,8]naphthyridin-4-amine hemihydrate as a solid, m.p. 81-84° C. Calculated for C17H27N5+½H2O: %C, 65.77; %H, 9.09; %N, 22.56; Found: %C, 65.57; %H, 9.15; %N, 22.53.

Provenance & Evidence