Water → 6,8-Difluoro-4-methylumbelliferone

HRID 355402ノート

反応式

HRID 355402 の反応式
[F:1][C:2]1[C:8]([OH:9])=[C:7]([F:10])[CH:6]=[CH:5][C:3]=1[OH:4].[C:11](OCC)(=[O:16])[CH2:12][C:13]([CH3:15])=O.O>CS(O)(=O)=O>[F:10][C:7]1[CH:6]=[C:5]2[C:3](=[C:2]([F:1])[C:8]=1[OH:9])[O:4][C:11](=[O:16])[CH:12]=[C:13]2[CH3:15]

参加物

5

反応物 3

HCID 962WaterHCID 8868Ethyl AcetoacetateHCID 108445152,4-Difluororesorcinol2 回

生成物 1

HCID 101767076,8-Difluoro-4-methylumbelliferone収率 49%

試薬・触媒・溶媒 1

HCID 6395Methanesulfonic Acid溶媒

実験手順

A solution of 2,4-difluororesorcinol (Compound 4; 1.00 g, 8.76 mmol) and ethyl acetoacetate (1.14 g, 8.76 mmol) in 5 mL methanesulfonic acid is kept at room temperature for 24 hours, then poured into water (75 mL). The resulting precipitate is collected, rinsed with water and dried, giving 0.91 g of Compound 5 as a tan powder. An analytical sample is prepared by crystallization from light petroleum ether/methanol, giving the Compound 5 as colorless needles. UV-vis (pH 7 buffer): 358 nm, ε=17,700 cm-1M-1 ; ex/em 358/452 nm. 1H NMR (CDCl3) δ7.12 (dd, 1H), 6.27 (s, 1H), 2.38 (s, 3H). 19F NMR (CDCl3) Φ 136.5 (t, 1F), 152.8 (t, 1F).

後処理

  1. customThe resulting precipitate is collected
  2. washrinsed with water
  3. customdried

出典と根拠

ORDレコード
ord-6eb8de7e19f84a0b8de9ff8643b3e1cb
出典データセット
uspto-grants-1998_11
特許番号
US05830912

反応ノート

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