Sodium Carbonate → Methyl 3-methyl-1-benzofuran-6-carboxylate

Temperature

80 °C

Methyl 3-(allyloxy)-4-iodobenzoate (2.0 g, 6.28 mmol) is dissolved in DMF (15 ml), treated with Pd(OAc)2 (71 mg, 0.31 mmol), Na2CO3 (1.67 g, 15.7 mmol), sodium formate (427 mg, 6.28 mmol), and n-Bu4NCl.H2O (1.92 g, 6.92 mmol) and stirred at 80° C. for 2 days. The mixture is then filtered, the liquor is diluted with EtOAc (75 ml) and washed with 50% saturated NaCl (4×25 ml) followed by 5% HCl (25 ml). The organic layer is dried (Na2SO4), filtered, and concentrated to a brown oil. The crude material is chromatographed over 50 g slurry-packed silica gel, eluting with 20% EtOAc/hexane. The appropriate fractions are combined and concentrated to afford 797 mg (67%) of methyl 3-methyl-1-benzofuran-6-carboxylate as a pale oil. HRMS (FAB) calcd for C11H10O3+H: 191.0708, found 191.0714 (M+H)+.

1. filtrationThe mixture is then filtered
2. additionthe liquor is diluted with EtOAc (75 ml)
3. washwashed with 50% saturated NaCl (4×25 ml)
4. dry with materialThe organic layer is dried (Na2SO4)
5. filtrationfiltered
6. concentrationconcentrated to a brown oil
7. customThe crude material is chromatographed over 50 g slurry-packed silica gel
8. washeluting with 20% EtOAc/hexane
9. concentrationconcentrated

ORD record

ord-aad4a5cd9e014d83a0ae4bdefd50e538

Source dataset

uspto-grants-2005_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06894042B2