Hydrochloric Acid → 3-bromo-1-(tetrahydro-2H-pyran-2-yl)-1H-indazole-5-carboxamide

Participants

Reaction Conditions

Reaction Steps

To a solution of 3-bromo-1-perhydro-2H-pyran-2-yl-1H-indazole-5-carbonitrile (2.6 g, 8.48 mmol) in 20 mL of ethanol was added 20 mL of commercial solution of hydrogen peroxide (30%) and 1.8 mL of aqueous solution of sodium hydroxide (6.0 N). The suspension was heated to 50° C. for 20 min. The reaction mixture was cooled down and neutralized with 6.0 N aqueous HCl. Further precipitation was observed upon addition of water (20 mL). The solid was collected by filtration, washed with small portions of water and dried in a vacuum oven at 40° C. (2.6 g, 95% yield) 1H NMR (CDCl3) δ 8.2 (s, 1H), 8.0 (d, 1H), 7.7 (br s, 1H), 7.6 (d, 1H), 6.4 (br s, 1H), 5.7 (dd, 1H), 4.0 (m, 1H), 3.75 (m, 1H), 2.5 (m, 1H), 2.0 (m, 2H), 1.7 (m, 3H); ES-MS (m/z) 276 [M+H]+.

Provenance & Evidence