反应详情

Ozone was bubbled through a solution of methyl 3-fluoro-2-vinylisonicotinate (1.4 g, 7.73 mmol, from Step 2) in methylene chloride (100 mL) at −78° C. until the blue color of excess ozone persisted. Nitrogen was bubbled through the solution for 1 minute to purge excess ozone and then triphenylphosphine (3.9 g, 15 mmol) was added and the solution was warmed to room temperature and stirred overnight. The compound was dry loaded onto silica gel. Flash chromatography eluting with 40% ethyl acetate in hexanes afforded product (0.8 g, 57%) as an off-white crystalline solid. 1H NMR (300 MHz, CDCl3): δ 10.27 (s, 1H), 8.73 (d, 1H), 8.01 (dd, 1H), 4.01 (s, 3H).

1. customNitrogen was bubbled through the solution for 1 minute
2. customto purge excess ozone
3. customThe compound was dry
4. washFlash chromatography eluting with 40% ethyl acetate in hexanes afforded product (0.8 g, 57%) as an off-white crystalline solid