Acetic Acid → (2,2-Difluoro-ethyl)-(2-nitro-6,7,8,9-tetrahydro-5h-benzocyclohepten-7-yl)-amine

Participants

Reaction Steps

Charge 2-Nitro-5,6,8,9-tetrahydrobenzocyclohepten-7-one (750.00 mg, 3.6548 mmol) to Methylene chloride (20 mL, 300 mmol) and Acetic acid (200 uL, 4 mmol). Allow to stir for 5 min. Charge 2,2-difluorethylamine (0.292 ml, 3.65 mmol) and sodium triacetoxyborohydride (1.55 g, 7.31 mmol). Allow suspension to stir for 2.5 hours. LC at 2.5 hours conforms that starting ketone has been consumed. Pour reaction into 200 ml water and 100 ml saturated sodium bicarbonate solution and extract with 2×100 ml portions of methylene chloride. The combined organic was dried over magnesium sulfate, filtered and evaporated to a yellow oil (approximately 1.0 g). The resulting crude yellow oil was chromatographed on a 12 g Isco cartridge using a gradient of 0-60% EtOAc in hexanes as the eluent. (2,2-Difluoro-ethyl)-(2-nitro-6,7,8,9-tetrahydro-5H-benzocyclohepten-7-yl)-amine was isolated as a beige oil (625 mg, 63% yield). 1H-NMR (CDCl3) δ 7.98 (m, 2H), 7.24 (m, 1H), 5.82 (m, 1H), 3.02 (m, 4H), 2.88 (m, 1H), 2.76 (m, 2H), 2.08 (m, 2H), 1.38 (m, 2H). LC/MS (ESI+): 271 (M+H).

Provenance & Evidence