Cesium carbonate → methyl 5-(1H-pyrazol-4-yl)thiophene-3-carboxylate

HRID 2068636ノート

反応式

HRID 2068636 の反応式
[CH3:1][O:2][C:3]([C:5]1[CH:9]=[C:8](Br)[S:7][CH:6]=1)=[O:4].C(OC([N:18]1[CH:22]=[C:21](B2OC(C)(C)C(C)(C)O2)[CH:20]=[N:19]1)=O)(C)(C)C.C(=O)([O-])[O-].[Cs+].[Cs+]>COCCOC.O.C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1.C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1.C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1.C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1.[Pd]>[CH3:1][O:2][C:3]([C:5]1[CH:9]=[C:8]([C:21]2[CH:22]=[N:18][NH:19][CH:20]=2)[S:7][CH:6]=1)=[O:4]

参加物

7

反応物 3

HCID 10796Cesium carbonateHCID 16217654tert-butyl 4-(tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazole-1-carboxylateHCID 45873035Methyl 5-bromothiophene-3-carboxylate

生成物 1

HCID 58110358methyl 5-(1H-pyrazol-4-yl)thiophene-3-carboxylate

試薬・触媒・溶媒 3

HCID 11979704Tetrakis(triphenylphosphine)palladium触媒HCID 962Water溶媒2 回HCID 80711,2-Dimethoxyethane溶媒

反応条件

温度
140 °C

実験手順

5-Bromo-thiophene-3-carboxylic acid methyl ester (1.29 g, 5.84 mmol) was dissolved in DME (13.5 mL), IMS (4.5 mL) and water (2 mL) and), 4-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-pyrazole-1-carboxylic acid tert-butyl ester (1.89 g, 6.43 mmol) and caesium carbonate (2.85 g, 8.77 mmol) were added followed by palladium tetrakis(triphenylphosphine) (0.675 g, 5.84 mmol). The reaction mixture was heated by microwave irradiation at 140° C. for 20 minutes and then diluted with water and extracted with DCM (×3). The organic solution was dried over sodium sulfate, filtered and the solvent evaporated. The residue was purified by chromatography on a silica II cartridge, eluting with 10 to 50% ethyl acetate in cyclohexane. The fractions containing the desired product were concentrated under vacuum to give 5-(1H-pyrazol-4-yl)-thiophene-3-carboxylic acid methyl ester as a white, flocculent solid (0.728 g).

後処理

  1. extractionextracted with DCM (×3)
  2. dry with materialThe organic solution was dried over sodium sulfate
  3. filtrationfiltered
  4. customthe solvent evaporated
  5. customThe residue was purified by chromatography on a silica II cartridge
  6. washeluting with 10 to 50% ethyl acetate in cyclohexane
  7. additionThe fractions containing the desired product
  8. concentrationwere concentrated under vacuum

出典と根拠

ORDレコード
ord-315b1c2fc9da4512be22d1406aa85878
出典データセット
uspto-grants-2012_10
特許番号
US08299063B2

反応ノート

読み込み中…