반응 #5031

ord-d6f8a145407c4859b6e938637fa82e5b

반응 조건

상세 조건
See reaction.notes.procedure_details.

후처리

  1. 1
    기타The pH of reaction mixture
  2. 2
    추출the mixture extracted with 250 ml ethyl acetate
  3. 3
    추출The aqueous layer was further extracted with 2×50 ml of 1:1 THF
  4. 4
    건조dried over Na2SO4
  5. 5
    기타evaporated to a solid, which
  6. 6
    기타was recrystallized from ethyl acetate
  7. 7
    기타to yield
  8. 8
    기타purified title product, 17.8 g (50.7%)

실험 절차

Under nitrogen, 14 g (0.29 mmol) of 50% NaH in oil was washed with 2×40 ml of hexane and then suspended in 90 ml of anhydrous tetrahydrofuran (THF). To this slurry at 0° C. was added dropwise a solution of ethyl 2-(2-amino-4-thiazolyl)acetate (27 g, 0.145 mmol) in 290 ml of anhydrous THF, followed by ethyl formate (21.5 g, 0.29 mmol), and the mixture stirred at room temperature for 18 hours. The pH of reaction mixture was adjusted to 7 by the addition of 50% aqueous acetic acid and the mixture extracted with 250 ml ethyl acetate. The aqueous layer was further extracted with 2×50 ml of 1:1 THF:ethyl acetate. The extracts were combined, dried over Na2SO4 and evaporated to a solid, which was recrystallized from ethyl acetate to yield purified title product, 17.8 g (50.7%); m.p. 179°-180° C.; 1H-nmr (CDCl3 -d6 -DMSO) 1.33 (t, 3H), 4.16 (q, 2H), 7.50 (s, 1H), 8.00 (s, 1H), 8.53 (s, 1H).

출처

DOI: 10.6084/m9.figshare.5104873.v1특허: US05242913uspto-grants-1993_09