3-(4-chloro-2-fluorophenyl)-3-oxopropanenitrile

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixture of (E)-3-(dimethylamino)acrylaldehyde (3.26 g, 32.9 mmol), the product from Step 1 (5.00 g, 25.3 mmol) and acetic acid (7.24 mL, 127 mmol) in DMF (40 mL) was heated to 120° C. for 48 h and cooled to room temperature. Ethyl acetate (400 mL) was added and the mixture washed with saturated NaHCO3 (40 mL), water (40 mL), brine (40 mL), dried (MgSO4) and concentrated. The residue was purified by flash column chromatography (silica, 10-40% ethyl acetate in hexanes) to provide 8-chloro-5H-chromeno[2,3-b]pyridin-5-one (600 mg, 10%). MS (ES+) m/z: 232 (M+H). the mixture washed with saturated NaHCO3 (40 mL), water (40 mL), brine (40 mL) dried (MgSO4) concentrated The residue was purified by flash column chromatography (silica, 10-40% ethyl acetate in hexanes)

Conditions: temp:-78.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A 1.6 M hexane solution of n-butyllithium (39.8 mL, 63.6 mmol) was added to a solution of diisopropylamine (9.45 mL, 66.3 mmol) in THF (100 mL) at −78° C. over 10 min. The resultant solution was stirred at 0° C. for 30 min and cooled to −78° C. Acetonitrile (3.32 mL, 63.6 mmol) dropwise. The mixture was stirred at −78° C. for 30 min and then added a solution of 4-chloro-2-fluorobenzoate (5.00 g, 26.5 mmol) in THF (5 mL) at −78° C. dropwise. After stirring for 1 h at −78° C., the reaction mixture was quenched with brine (20 mL), warmed to room temperature and adjusted to pH 1-2 with 1N aqueous HCl. Following addition of ethyl acetate (400 mL), the mixture was washed with water (40 mL), brine (40 mL), dried (MgSO4) and concentrated to provide 3-(4-chloro-2-fluorophenyl)-3-oxopropanenitrile as tan solid (5.10 g, 97%). MS (ES+) m/z: 198 (M+H). After stirring for 1 h at −78° C. the reaction mixture was quenched with brine (20 mL) warmed to room temperature addition of ethyl acetate (400 mL) the mixture was washed with water (40 mL), brine (40 mL) dried (MgSO4) concentrated