1,8-Diazabicyclo(5.4.0)undec-7-ene → 4H-Pyrano(2,3-b)pyridine, 6-bromo-2-(3,4-dichlorophenyl)-

Participants

Reaction Steps

To a solution of 2.9 g of 6-bromo-2-(3,4-dichlorophenyl)-2H-pyrano[2,3-b]pyridine in 40 ml of tetrahydrofuran was added 0.5 ml of 1,8-diazabicyclo[5.4.0]undec-7-ene. After 1 hour at 25° C., the reaction mixture was partitioned between ethyl acetate and aqueous saturated ammonium chloride solution. The ethyl acetate layer was dried over magnesium sulfate and the solvent was evaporated to leave a solid residue. This was recrystallized from ethanol to give 6-bromo-2-(3,4-dichlorophenyl)-4H-pyrano[2,3-b]pyridine melting at about 138°-139.5° C.

Provenance & Evidence