Nitric Acid → 2-Bromo-3-methoxy-6-nitropyridine

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To a 500 mL round bottomed flask fitted with a Teflon stir bar and a thermometer was added 90 mL of concentrated sulphuric acid and 37.6 g of 2-bromo-3-methoxypyridine (200 mmol). The flask was warmed in an oil bath to 60° C. Added slowly over 1h 16.5 mL (350 mmol) of fuming nitric acid (90%, d=1.50). Maintain the temperature between 60 and 70° during the addition. Stir at 60° for 3h after the addition was complete, then at room temperature overnight. By TLC (70/30 hex/EtOAc) is consumed. The product mixture was poured into 600 mL of ice/water, from which the product precipitated. This material was filtered, washed with 3×200 mL of cold water and then 100 mL of saturated sodium bicarbonate. After drying in the filter funnel in a stream of air, the remaining water was removed under reduced pressure, to give 16.5 g of a solid. H NMR (400 MHz, CDCl3): δ 8.27(d, J=8 Hz,1H); 6.32(d, J=8 Hz,1H); 4.06(s, 3H).

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