Toluene → Methyl 2-(4-acetyl-5-methyl-1H-pyrazol-1-yl)acetate

HRID 2425547ノート

反応式

HRID 2425547 の反応式
[C:1]([C:4]1[CH:5]=[N:6][N:7]([CH2:10][C:11]([OH:13])=[O:12])[C:8]=1[CH3:9])(=[O:3])[CH3:2].[C:14]1(C)C=CC=CC=1.C[Si](C=[N+]=[N-])(C)C.CCOCC>CO>[C:1]([C:4]1[CH:5]=[N:6][N:7]([CH2:10][C:11]([O:13][CH3:14])=[O:12])[C:8]=1[CH3:9])(=[O:3])[CH3:2]

参加物

6

反応物 4

HCID 1140TolueneHCID 3283Diethyl EtherHCID 167693TrimethylsilyldiazomethaneHCID 632769652-(4-acetyl-5-methyl-1H-pyrazol-1-yl)acetic acid

生成物 1

HCID 67181907Methyl 2-(4-acetyl-5-methyl-1H-pyrazol-1-yl)acetate収率 99%

試薬・触媒・溶媒 1

HCID 887Methanol溶媒

実験手順

To a solution of 2-(4-acetyl-5-methyl-1H-pyrazol-1-yl)acetic acid (1.17 g, 6.42 mmol, as a mixture of regioisomers from the previous step) in MeOH (8.8 ml)-Toluene (30.6 ml) was added a 2 M solution of (trimethylsilyl)diazomethane in ether (4.8 ml, 9.6 mmol) dropwise at 0° C. The resulting solution was allowed to warm to rt and stirred for 120 min. The reaction was quenched by addition of AcOH (3 ml) and the solvent was concentrated in vacuo. The crude product was purified by silica gel column chromatography (CH2Cl2:MeOH=30:1) to give the desired product along with a mixture of regioisomers (>99% yield). 1H NMR (270 MHz, CDCl3) δ 2.45 (3H, s), 2.53 (3H, s), 3.79 (3H, s), 4.90 (2H, s), 7.88 (1H, s).

後処理

  1. customThe reaction was quenched by addition of AcOH (3 ml)
  2. concentrationthe solvent was concentrated in vacuo
  3. customThe crude product was purified by silica gel column chromatography (CH2Cl2:MeOH=30:1)

出典と根拠

ORDレコード
ord-482840abe9c74daa8b9da94f887c52c0
出典データセット
uspto-grants-2011_06
特許番号
US07964732B2

反応ノート

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