Dimethylformamide → 4-(Pyridin-4-yloxy)benzene-1-sulfonyl chloride hydrochloride

Participants

Reaction Conditions

Reaction Steps

To a suspension of 4-[(pyrid-4-yl)oxy]benzenesulfonic acid 3a (1.3 kg) in acetonitrile (8 L), was added N,N-dimethylformamide (12.35 mL) and the viscous reaction mixture was heated to 75° C. Thionyl chloride (756 mL) was added to the reaction mixture over 30 minutes. The reaction mixture slowly became less viscous and became homogeneous after 45 minutes, which indicated the reaction was complete. A portion of the solvent (4 L) was evaporated under vacuum and tert-butyl methyl ether (4 L) was added. The resulting slurry was filtered under inert atmosphere. The filter cake was rinsed with tert-butyl methyl ether (2 L) and the solid dried under vacuum to yield 4-[(pyrid-4-yl)oxy]benzenesulfonyl chloride hydrochloride 4a (1.35 kg) as a fluffy off-white solid of pearlescent flakes: mp 182° C.; 1H NMR (300 MHz, CDCl3): δ 8.87 (d, J=7 Hz, 2H), 8.24 (d, J=8.5 Hz, 2H), 7.50 (d, J=8.5 Hz, 2H), 7.43 (d, J=7 Hz, 2H).

Provenance & Evidence