Sulfuric Acid → 2,6-Difluoro-4-methylbenzaldehyde

温度

-50 °C

To a solution of 1,3-difluoro-5-methylbenzene (10.2 g, 80 mmol) in anhydrous ether (80 mL) was added n-BuLi (2.5 M solution in hexane, 48 ml, 120 mmol) over a 20 min period while the internal temperature was maintained at around −50° C. After stirring at that temperature for 1.5 hr, DMF (14.6 g, 200 mmol) was added over a 20 min period. After stirring at the same temperature for an additional 1.5 h, the reaction mixture was slowly poured into 1N aqueous sulfuric acid (300 mL) and extracted with ether three times. The combined organic layers were washed with brine, dried over anhydrous MgSO4, filtered and concentrated to give the title compound (11.2 g, 90%). 1H-NMR (500 MHz, CDCl3): δ 10.25 (s, 1H), 6.75 (d, 2H, J=9.9 Hz), 2.39 (s, 3H).

1. stirringAfter stirring at the same temperature for an additional 1.5 h
2. extractionextracted with ether three times
3. washThe combined organic layers were washed with brine
4. dry with materialdried over anhydrous MgSO4
5. filtrationfiltered
6. concentrationconcentrated

ORDレコード

ord-c60be9c73c4f4f05ab691443c344a7c6

出典データセット

uspto-grants-2011_09

DOI

10.6084/m9.figshare.5104873.v1

特許番号

US08017605B2