反应详情

To a solution of 4-iodopicolinic acid 11a (7.0 g, 18.6 mmol) in MeOH (70 mL) at 23° C. was added concentrated sulfuric acid (350 μL), and the reaction mixture was refluxed for 48 h. The reaction mixture was cooled to room temperature and concentrated to yield the desired product 4-iodopicolinic acid methyl ester 11b (4.4 g, 90%) as a yellow oil; 1H NMR (300 MHz, CDCl3) δ 8.52 (t, J=0.6, 1.5, 1), 8.40 (d, J=5.1, 1), 7.86–7.88 (dd, J=0.6, 5.1, 1), 4.02 (s, 3); MS (ESPOS): 263.9 [M+H]; 285.9 [M+Na].

1. temperaturethe reaction mixture was refluxed for 48 h
2. concentrationconcentrated