Synthesis
In a screw cap vial, o-phenylenediamine (1 mmol) was dissolved in difluoroacetic acid (2 mL, 0.5 M) and the reaction mixture was stirred at 70 °C for 16 hours. After completion of the reaction, the difluoroacetic acid was removed by evaporation under reduced pressure and the crude product was purified by silica gel column chromatography to afford 2-(difluoromethyl)-1H-benzo[d]imidazole.
References
[1] Tetrahedron Letters, 2013, vol. 54, # 3, p. 201 - 204
[2] Patent: US2007/244110, 2007, A1. Location in patent: Page/Page column 4
[3] ACS Medicinal Chemistry Letters, 2013, vol. 4, # 2, p. 206 - 210
[4] Tetrahedron Letters, 2007, vol. 48, # 18, p. 3251 - 3254
[5] Patent: WO2013/123634, 2013, A1. Location in patent: Paragraph 0027