2-Bromo-4-fluorobenzene-1-sulfonyl chloride → methyl 7-(2-bromo-4-fluorobenzenesulfonylamino)-4H-5-oxa-3,9b-diazacyclopenta[a]naphthalene-6-carboxylate

Participants

Reaction Steps

A mixture of methyl 7-amino-4H-5-oxa-3,9b-diazacyclopenta[a]naphthalene-6-carboxylate (Intermediate 26, 0.379 g) and 2-bromo-4-fluorobenzenesulfonyl chloride (0.466 g) in pyridine (10 mL) and DCM (10 mL) was stirred at room temperature for 17 hours. A further amount of 2-bromo-4-fluorobenzenesulfonyl chloride (0.190 g) was added and the mixture was stirred at room temperature for 5 hours. The resultant mixture was concentrated in vacuo and the residue was dissolved in DCM and water and passed through a phase separator. The filtrate was concentrated in vacuo and the residue was purified by chromatography on silica, eluting with ethyl acetate to give a white solid which was triturated with ether to give methyl 7-(2-bromo-4-fluorobenzenesulfonylamino)-4H-5-oxa-3,9b-diazacyclopenta[a]naphthalene-6-carboxylate (0.603 g) as an off-white solid.

Provenance & Evidence