Methanol → Clopyralid-methyl

Participants

Reaction Steps

To a 3-neck round bottom flask equipped with a reflux condenser was added 3,6-dichloropyridine-2-carboxylic acid (50.0 g, 260.42 mmol) in methanol (200 mL). HCl(g) was bubbled in until solution became saturated and stirred at room temperature for 2 hr. The solution was concentrated to dryness in vacuo. Diethyl ether was added to make a slurry that was subsequently added to a flask filled with a 1:1 mixture of saturated sodium bicarbonate/diethyl ether and stirred for 10 min. The aqueous phase was extracted with diethyl ether (3×300 mL). The combined extracts were dried (MgSO4) and concentrated to give 46.6 g of a light yellow solid. 1H NMR(CDCl3): δ 4.00 (s, 3H); 7.41 (d, 1H); 7.80 (d, 1H).

Provenance & Evidence