2-Bromo-4-fluorobenzene-1-sulfonyl chloride → methyl 7-(2-bromo-4-fluorobenzenesulfonylamino]-4H-benzo[b]pyrrolo[1,2-d][1,4]oxazine-6-carboxylate

Participants

Reaction Steps

Methyl 7-amino-3a,4-dihydro-1H-benzo[b]pyrrolo[1,2-d][1,4]oxazine-6-carboxylate (Intermediate 17, 0.370 g) was suspended in a mixture of DCM (6 mL) and pyridine (2.43 mL) and 2-bromo-4-fluorobenzenesulfonyl chloride (0.493 g) was added. The resultant deep red solution was stirred at room temperature overnight then concentrated in vacuo. The residue was diluted with DCM and water and passed through a phase separator. The organic layer was concentrated in vacuo and the residue was purified by chromatography on silica, eluting with a mixture of ethyl acetate and cyclohexane with a gradient of 5-30% to give methyl 7-(2-bromo-4-fluorobenzenesulfonylamino]-4H-benzo[b]pyrrolo[1,2-d][1,4]oxazine-6-carboxylate (0.107 g) as a white solid.

Provenance & Evidence