Ethyl Acetate → 2,3-Dihydro-1-benzofuran-7-carbaldehyde

Temperatur

0 °C

2,3-Dihydrobenzo[b]furan (Maybridge Chemicals) (25 g, 0.21 mole) was taken up in DCM (500 ml) and stirred under nitrogen at 0° C. SnCl4 (36.5 ml, 0.3 mole) was added in one portion to produce a pale yellow solution. Dichloromethyl methyl ether (18.8 ml, 0.21 mole) was then added and the solution stirred for 30 min, after which time the cooling bath was removed and the reaction poured onto ice-water (1000 ml). The organic layer was separated, washed with water (2×100 ml), 2N HCl (100 ml) and brine (50 ml), and then charcoal (30 g) and Na2SO4 were added to the solution. Filtration through Celite and evaporation gave a black oil, which was subjected to flash chromatography using 7-10% EtOAc in pentane to give the title product (190 mg, 0.01%); 1HNMR (400 MHz, CDCl3) δ: 3.24 (t, 2H), 4.75 (t, 2H), 6.93 (t, 1H), 7.40 (d, 1H), 7.59 (d, 1H), 10.2 (s, 1H); LRMS: (M+H) 149, TS+. Anal. Found: C, 72.98; H, 5.46%. C9H8O2 requires C, 72.96; H, 5.44%.

1. customto produce a pale yellow solution
2. stirringthe solution stirred for 30 min
3. customafter which time the cooling bath was removed
4. additionthe reaction poured onto ice-water (1000 ml)
5. customThe organic layer was separated
6. washwashed with water (2×100 ml), 2N HCl (100 ml) and brine (50 ml)
7. additioncharcoal (30 g) and Na2SO4 were added to the solution
8. filtrationFiltration
9. customthrough Celite and evaporation
10. customgave a black oil, which

ORD-Eintrag

ord-7f849dc30a71469c9d1563b5e480598b

Quelldatensatz

uspto-grants-2003_12

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US06660756B2