Hydrogen Bromide → 6-Bromo-4-methoxypyrazolo[1,5-a]pyridine

HRID 1253452ノート

反応式

HRID 1253452 の反応式
[Br:1][C:2]1[CH:3]=[C:4]([O:15][CH3:16])[C:5]2[N:6]([N:8]=[CH:9][C:10]=2C(OC)=O)[CH:7]=1.BrC1C2N(N=CC=2C(OC)=O)C=C(OC)C=1.Br.[OH-].[Na+]>C(OCC)(=O)C>[Br:1][C:2]1[CH:3]=[C:4]([O:15][CH3:16])[C:5]2[N:6]([N:8]=[CH:9][CH:10]=2)[CH:7]=1

参加物

6

反応物 4

HCID 260Hydrogen BromideHCID 14798Sodium HydroxideHCID 67207875HCID 67207875、化合物HCID 67374655HCID 67374655、化合物

生成物 1

HCID 446228256-Bromo-4-methoxypyrazolo[1,5-a]pyridine

試薬・触媒・溶媒 1

HCID 8857Ethyl Acetate溶媒

反応条件

温度
100 °C

実験手順

A mixture of methyl 6-bromo-4-methoxypyrazolo[1,5-a]pyridine-3-carboxylate (4.33 g, 15.2 mmol) and methyl 4-bromo-6-methoxypyrazolo[1,5-a]pyridine-3-carboxylate (1.44 g, 5.05 mmol) was suspended in hydrobromic acid (100 ml, 884 mmol) and heated to 100° C. for 60 minutes. The mixture was cooled to 0° C. and carefully quenched via the addition of 1N aqueous sodium hydroxide (152 ml, 909 mmol). The reaction mixture was diluted in ethyl acetate, washed with 1N aqueous sodium hydroxide and brine then dried over sodium sulfate, filtered and concentrated. The residue was purified by column chromatography on silica gel (Ethyl acetate/isohexane gradient) to give 6-bromo-4-methoxypyrazolo[1,5-a]pyridine (faster eluting isomer) and 4-bromo-6-methoxypyrazolo[1,5-a]pyridine (slower eluting isomer).

後処理

  1. temperatureThe mixture was cooled to 0° C.
  2. washwashed with 1N aqueous sodium hydroxide and brine
  3. dry with materialthen dried over sodium sulfate
  4. filtrationfiltered
  5. concentrationconcentrated
  6. customThe residue was purified by column chromatography on silica gel (Ethyl acetate/isohexane gradient)

出典と根拠

ORDレコード
ord-79c3fa0785554c43861c5c6594a72f5d
出典データセット
uspto-grants-2013_06
特許番号
US08455477B2

反応ノート

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