Sodium Hydroxide → [4-(8-Bromo-2-oxo-2,3-dihydro-imidazo[4,5-c]quinolin-1-yl)-3-methyl-pyrazol-1-yl]-acetic acid

Participants

Reaction Steps

To a mixture of [4-(8-bromo-2-oxo-2,3-dihydro-imidazo[4,5-c]quinolin-1-yl)-3-methyl-pyrazol-1-yl]-acetic acid methyl ester (Stage 101.1.3, 3.22 g, 7.73 mmol) and tetrabutylammonium (250 mg, 0.773 mmol) in CH2Cl2 (150 ml) was added 1 M aqueous NaOH (80 ml). The reaction mixture was energetically stirred for 4 h 30 at rt. The organic layer was separted and the aqueous layer washed with CH2Cl2 (2×), adjusted to pH 4 with concentrated aqueous HCl and extracted with n-butanol (5×). The combined organic layers were washed with brine adjusted to pH 4 with HCl and evaporated to dryness. The residue was dry loaded on Isolute, washed with water/1-propanol 3% and eluted with acetonitrile/1-propanol 3% on reverse phase silica gel plug. To acetonitrile filtrate was added water and solution was concentrated. The formed precipitate was filtered, washed with water and dried to give the title compound as a yellow solid. (HPLC: tR 2.08 min (Method A); M+H=402, 404 Br-Pattern MS-ES)

Provenance & Evidence