Hydrochloric Acid → 2-Fluoro-4-iodopyridine-3-carboxylic acid

Participants

Reaction Steps

To a stirred solution of 2-fluoro-4-iodopyridine-3-carboxaldehyde (10.0 g, 39.8 mmol) in tert-butanol (350 mL) and water (100 mL) at room temperature were added 2-methyl-2-butene (42.1 ml, 398 mmol), sodium phosphate, monobasic, monohydrate (60.5 g, 438 mmol) and sodium chlorite (18.0 g, 199 mmol). The reaction mixture was stirred at room temperature for 75 min. The reaction mixture was diluted with dichloromethane and a 6M aqueous solution of hydrochloric acid was added until pH ˜2. The water layer was extracted with dichloromethane. The organic phase was dried over MgSO4, filtered and concentrated in vacuo. Purification by MPLC (CH2Cl2/MeOH+1% AcOH: 100/0 to 80/20) afforded 2-fluoro-4-iodonicotinic acid (10.63 g, 39.8 mmol, 100% yield). MS (ESI pos. ion) m/z: 268 (MH+). Calc'd exact mass for C6H3FINO2: 267.

Provenance & Evidence