Boron tribromide → HCID 178508190, compound

Participants

Reaction Steps

To a stirred suspension of 1-benzyl-2-ethoxy-1H-imidazo[4,5-c][1,5]naphthyridin-4-amine (1.3 g, 4 mmol) in dichloromethane (20 mL) was added boron tribromide (1M solution in dichloromethane, 10 mL, 10 mmol), and the reaction was stirred at room temperature. Additional aliquots of the boron tribromide solution (7.5 equivalents, 30 mmol total) were added to drive the reaction to completion. The reaction was concentrated under reduced pressure, and to it was added methanol (1 mL) followed by 6M HCl (100 mL). The reaction was heated at 50° C. for 2 hours, cooled in an ice bath, and adjusted to a basic pH by the addition of 6N NaOH. The product was extracted with dichloromethane and the organic layers were combined, dried (MgSO4), filtered, and evaporated to afford crude product. The product was purified by preparative HPLC (Analogix Separation System, and eluted with a gradient of 0-10% methanol in dichloromethane with 1% ammonium hydroxide) to provide a solid which was triturated with hot acetonitrile, filtered, and washed with ether to afford 4-amino-1-benzyl-1H-imidazo[4,5-c][1,5]naphthyridin-2-ol (196 mg) as a yellow solid, mp>250° C.; HRMS (ESI) calcd for C16H13N5O[M+H]+: 292.1198. found 292.1198.

Provenance & Evidence