3-Bromo-4-fluorobenzonitrile → HCID 21463658, compound

Participants

Reaction Conditions

Reaction Steps

A 100 mL 3-necked flask equipped with a stir bar, a condenser, and a nitrogen inlet was flushed with nitrogen and then charged with 3-bromo-4-fluorobenzonitrile (2.507 g, 1.23×10−2 mol), 4-trifluoromethoxyphenyl boronic acid (2.825 g, 1.23×10−2mol, 1.01 equiv), bis(triphenylphosphine)-palladium(II) chloride (2.0 mg, 2.85×10−6 mol, 0.02 mol %), and sodium bicarbonate (1.577 g, 1.82×10−2 mol, 1.5 equiv). The flask was then evacuated and purged with nitrogen three times, and charged with deoxygenated toluene (6 mL) and deoxygenated water (6 mL). The mixture was heated to 80° C. until HPLC analysis indicated the disappearance of the aryl bromide (less than 16 hours; HPLC conditions: Eclipse XDB-C8 (4.6 mm×150 mm), flow rate: 1.5 mL/min.; mobile phase: 80:20 water(0.1%H3PO4)/CH3CN to 20:80 in 8 minutes, hold to 15 minutes with the column at 35° C. and UV detection: 210 nm. Retention time for the product is 8.88 min, retention time for aryl bromide is 6.47 min, retention time for excess boronic acid is 5.64 min, and retention time for homocoupled product is 10.58 minutes). The reaction was cooled to room temperature and the phases were separated. The organic phase was filtered through a plug of silica (2.5 g) and the silica plug was washed with toluene (25 mL). The filtrate was concentrated to provide the desired product (3.472 g, 92% potency, 93% potency adjusted yield). HRMS (FAB) calcd. for C14H7F4NO (M+H)+: 282.0542, found 282.0536; 1H NMR (CDCl3) δ 7.76 (dd, 1H), 7.68 (ddd, 1H), 7.56 (m, 2H), 7.34 (m, 2H), 7.30 (dd, 1H); 13C (CDCl3) δ 161.9, 149.5, 134.9, 133.5, 131.9, 130.4, 129.5, 121.2 (2), 120.4, 117.8, 117.7, 109.1; IR (KBr) 2230, 1514, 1490, 1265, 1256, 1223, 1210, 1157; Analytical: Pd 6 ppm, B <30ppm, Na <1ppm; mp 63.5-64.2° C.

Provenance & Evidence