반응 #317418

ord-b5e9d51b509046dc8282c3c78224c971

반응 조건

온도
0°CELSIUS
상세 조건
See reaction.notes.procedure_details.

후처리

  1. 1
    기타The title compound was prepared
  2. 2
    온도to warm to room temperature
  3. 3
    기타The reaction mixture was partitioned between diethyl ether and water
  4. 4
    추출The aqueous layer was extracted with ether
  5. 5
    건조the combined organic layers were dried over sodium sulfate
  6. 6
    여과filtered
  7. 7
    기타evaporated under reduced pressure
  8. 8
    기타The N,N′-dimethylformamide was removed under high vacuum
  9. 9
    기타the material was absorbed onto silica gel

실험 절차

The title compound was prepared as described by Khatuya (Tetrahedron Letters (2001), 42(14), 2643-2644.). 2-Methyl-furan-3-carboxylic acid methyl ester (5.0 g, 35.7 mmol) was dissolved in N,N′-dimethylformamide (10 mL) and cooled to 0° C. N-bromosuccinimide (NBS) (15.88 g, 89.2 mmol) was added in portions. Approximately 6.5 grams of NBS were added over 45 minutes at which point it was determined by HPLC that complete formation of 5-bromo-2-methyl-furan-3-carboxylic acid methyl ester had occurred. The reaction was allowed to warm to room temperature and the remainder of the NBS was added over 1.5 hours. The reaction mixture was partitioned between diethyl ether and water. The aqueous layer was extracted with ether and the combined organic layers were dried over sodium sulfate, filtered, and evaporated under reduced pressure. The N,N′-dimethylformamide was removed under high vacuum and the material was absorbed onto silica gel and passed through a column of silica gel using 5% ethyl acetate in hexanes as the eluent. The title compound was obtained as a very pale greenish, waxy solid (4.86 g, 46%). 1H NMR (300.132 MHz, DMSO) δ 6.93 (s, 1H), 4.93 (s, 2H), 3.82 (s, 3H).

출처

DOI: 10.6084/m9.figshare.5104873.v1특허: US07566727B2uspto-grants-2009_07