Hydrochloric Acid → Furan, 2-[(1E)-2-nitroethenyl]-

Temperature

-5 °C

In a 1L 3-necked flask equipped with a mechanical stirrer, thermometer and a dropping funnel was placed 2-furaldehyde 32I (48 g, 0.5 mol) and nitromethane (30.5 g, 0.5 mol) in methanol (100 mL). The resulting mixture was cooled to −5° C. A solution of sodium hydroxide (21 g, 0.525 mol) in water (75 mL) was added at such a rate to maintain internal temperature at 0° C. (45 min). The resulting paste was stirred at 0° C. for 1 hr and then ice cold water (100 mL) was added to get a homogeneous mixture. This mixture was poured into a stirring cold solution of hydrochloric acid (100 mL of concentrate hydrochloric acid in 150 mL of water)over 20 min. After 30 min, yellow solid was collected, washed with water (250 mL) and treated with 2 g of charcoal (Norit A) in boiling ethanol (75 mL). Hot filtered through a pad of celite (7 g) in a steam jacketed Buchner funnel. The pad was washed with hot ethanol (15 mL). The filtrate was placed in a fridge for 1 hr and then yellow solid was collected and air dried to give 44 g (63% yield) of 33I. Hplc analysis showed a purity of 98%. NMR (CDCl3) δ 7.8(q, 2H), 7.8(S br, 1H), 7.1(d, 1H), 6.7–6.9(m, 1H).

1. customthermometer and a dropping funnel was placed
2. temperatureto maintain internal temperature at 0° C. (45 min)
3. customto get a homogeneous mixture
4. waitAfter 30 min
5. customyellow solid was collected
6. washwashed with water (250 mL)
7. additiontreated with 2 g of charcoal (Norit A)
8. filtrationHot filtered through a pad of celite (7 g) in a steam
9. washThe pad was washed with hot ethanol (15 mL)
10. waitThe filtrate was placed in a fridge for 1 hr
11. customyellow solid was collected
12. customair dried

ORD record

ord-c21a7c9974ac430295f2ab3b575d4429

Source dataset

uspto-grants-2006_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07115748B2