2-Aminopyridine → Methyl 3-methylimidazo[1,2-a]pyridine-2-carboxylate

HRID 1798714ノート

反応式

HRID 1798714 の反応式
Br[CH:2]([CH3:9])[C:3](=O)[C:4]([O:6][CH3:7])=[O:5].[NH2:10][C:11]1[CH:16]=[CH:15][CH:14]=[CH:13][N:12]=1>C(#N)C>[CH3:9][C:2]1[N:12]2[CH:13]=[CH:14][CH:15]=[CH:16][C:11]2=[N:10][C:3]=1[C:4]([O:6][CH3:7])=[O:5]

参加物

4

反応物 2

HCID 104392-AminopyridineHCID 11183175Methyl 3-bromo-2-oxobutanoate

生成物 1

HCID 57690029Methyl 3-methylimidazo[1,2-a]pyridine-2-carboxylate収率 30.7%

試薬・触媒・溶媒 1

HCID 6342Acetonitrile溶媒

実験手順

Methyl 3-bromo-2-oxobutanoate (6.5 g, 34.3 mmol) was added to a stirred solution of 2-aminopyridine (4.0 g, 42.5 mmol) in acetonitrile (100 ml). The mixture was heated at reflux for 14 h (the reaction was monitored by TLC). The mixture was concentrated in vacuo and the residue was diluted with water and the pH was to 7.5 using sodium bicarbonate solution. The mixture was extracted with EtOAc; the combined organics were dried over sodium sulfate, filtered and concentrated under reduced pressure. The residue was purified by flash column chromatography using 8% ethyl acetate in n-hexane and silica gel (230-400 mesh) to afford methyl 3-methylimidazo[1,2-a]pyridine-2-carboxylate (2.0 g, 25.1%) as a pale yellow solid. 1H NMR: 200 MHz, CDCl3: δ 7.95 (d, 1H), 7.7 (d, 1H), 7.25 (t, 1H), 6.8 (t, 1H), 4.0 (s, 3H), 2.8 (s, 3H). MS: [M+H]+: m/z=191.1.

後処理

  1. temperatureThe mixture was heated
  2. temperatureat reflux for 14 h (the reaction
  3. concentrationThe mixture was concentrated in vacuo
  4. additionthe residue was diluted with water
  5. extractionThe mixture was extracted with EtOAc
  6. dry with materialthe combined organics were dried over sodium sulfate
  7. filtrationfiltered
  8. concentrationconcentrated under reduced pressure
  9. customThe residue was purified by flash column chromatography

出典と根拠

ORDレコード
ord-f240631c62f7479589282c7522edc3bd
出典データセット
uspto-grants-2013_01
特許番号
US08343973B2

反応ノート

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