Dimethyl Sulfoxide → HCID 22481734, compound

Temperature

-78 °C

Oxalyl chloride (0.1 ml, 1.15 mmol) is dissolved in CH2Cl2 (2 ml) in a dry flask under nitrogen and cooled to −78° C. DMSO (0.16 ml, 2.3 mmol) is added drop-wise, and the mixture stirred for 30 min, while maintaining the temperature. Methyl 2-(1-hydroxyethyl)-1-benzofuran-6-carboxylate (220 mg, 1.0 mmol) is dissolved in CH2Cl2 (2 ml) and added drop-wise to the mixture, and the solution stirred for 1 h at −78° C. TEA (0.69 ml, 5.0 mmol), is added drop-wise and the reaction is stirred for an additional 30 min. The reaction is then warmed to 0° C. and stirred for another 30 min. The reaction is washed with saturated NaHCO3 (40 ml), and the organics are dried (K2CO3), filtered, and concentrated to a yellow solid. The crude material is chromatographed over 25 g slurry-packed silica gel, eluting with 20% EtOAc/hexane. The appropriate fractions are collected and concentrated to afford 174 mg (80%) of methyl 2-acetyl-1-benzofuran-6-carboxylate as a pale yellow solid. HRMS (FAB) calcd for C12H10O4+H: 219.0657, found 219.0667 (M+H)+.

1. temperaturewhile maintaining the temperature
2. additionadded drop-wise to the mixture
3. stirringthe solution stirred for 1 h at −78° C
4. stirringthe reaction is stirred for an additional 30 min
5. temperatureThe reaction is then warmed to 0° C.
6. stirringstirred for another 30 min
7. washThe reaction is washed with saturated NaHCO3 (40 ml)
8. dry with materialthe organics are dried (K2CO3)
9. filtrationfiltered
10. concentrationconcentrated to a yellow solid
11. customThe crude material is chromatographed over 25 g slurry-packed silica gel
12. washeluting with 20% EtOAc/hexane
13. customThe appropriate fractions are collected
14. concentrationconcentrated

ORD record

ord-9f3edab1d9c8426fad4907b337e0ba19

Source dataset

uspto-grants-2005_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06894042B2