1,2-Difluorobenzene → HCID 15093857, compound

Participants

Reaction Conditions

Reaction Steps

A mechanically stirred mixture of 49.0 g (0.43 mole) of 1,2-difluorobenzene, 20.6 g (0.19 mole) of pyridine-4-carboxaldehyde and 80 ml of concentrated H2SO4 was heated at 70° C. for 21 hours. The reaction mixture was poured over ice, and the icy mixture was made basic with 50% NaOH. The resulting mixture was extracted with CH2Cl2 and the CH2Cl2 solution was dried (MgSO4). The solvent was removed in vacuo to give 54.94 g (89.8%) of a solid. This was recrystallized from a mixture of CH2Cl2 and hexane to give 44.82 g (74.3%) of a crystalline solid, mp 79°-82° C. Proton NMR showed that this sample contained ~5% of the 2,3-difluoro isomer.

Provenance & Evidence