Triphenylphosphine → 2,5-Difluoro-9H-carbazole

Participants

Reaction Steps

A solution of 2,4′-difluoro-6-nitro-1,1′-biphenyl (1.100 g, 4.7 mmol) and triphenylphosphine (3.067 g, 11.7 mmol) in anhydrous 1,2-dichlorobenzene (2 mL) was heated to 175° C. in a microwave reactor for 4 hrs. The mixture was cooled to room temperature and concentrated in vacuo. The crude residue was then purified by silica gel chromatography (5-50% methylene chloride/hexanes) to afford the product as a white solid (0.84 g, 88%). 1H NMR (CDCl3, 300 MHz) δ 8.17 (br s, 1H), 8.12 (dd, 1H, J=8.7, 5.1 Hz), 7.33 (td, 1H, J=8.1, 5.1 Hz), 7.20 (d, 1H, J=8.1 Hz), 7.12 (dd, 1H, J=9.3, 2.4 Hz), 7.02 (td, 1H, J=9.3, 2.4 Hz), 6.93 (dd, 1H, J=9.6, 7.8 Hz).

Provenance & Evidence