Chloroform → 5-(4-Acetoxyphenyl)-2-acetylamino-3-benzylpyrazine

HRID 1970793ノート

反応式

HRID 1970793 の反応式
[NH2:1][C:2]1[C:7]([CH2:8][C:9]2[CH:14]=[CH:13][CH:12]=[CH:11][CH:10]=2)=[N:6][C:5]([C:15]2[CH:20]=[CH:19][C:18]([OH:21])=[CH:17][CH:16]=2)=[CH:4][N:3]=1.[CH:22](Cl)(Cl)Cl.[C:26](Cl)(=[O:28])[CH3:27].[C:30](=[O:33])(O)[O-].[Na+]>N1C=CC=CC=1>[C:26]([O:21][C:18]1[CH:17]=[CH:16][C:15]([C:5]2[N:6]=[C:7]([CH2:8][C:9]3[CH:10]=[CH:11][CH:12]=[CH:13][CH:14]=3)[C:2]([NH:1][C:30](=[O:33])[CH3:22])=[N:3][CH:4]=2)=[CH:20][CH:19]=1)(=[O:28])[CH3:27]

参加物

6

反応物 4

HCID 6212ChloroformHCID 6367Acetyl chlorideHCID 1937434-(5-Amino-6-(phenylmethyl)-2-pyrazinyl)phenolHCID 516892Sodium Bicarbonate

生成物 1

HCID 670026125-(4-Acetoxyphenyl)-2-acetylamino-3-benzylpyrazine収率 57.8%

試薬・触媒・溶媒 1

HCID 1049Pyridine溶媒

実験手順

Under an argon atmosphere, 2-amino-3-benzyl-5-(4-hydroxyphenyl)pyrazine (coelenteramine) (c-5) (prepared by the method described in Adamczyk, M. et al., Org. Prep. Proced. Int., 33, 477-485 (2001)) (471 mg, 1.70 mmol) was dissolved in pyridine (3.6 mL) and chloroform (9 mL) and cooled to 0° C. To this was added acetyl chloride (910 μL, 12.8 mmol) and stirred for an hour after warming to room temperature. To this was added saturated aqueous solution of sodium bicarbonate to stop the reaction and extracted 3 times with dichloromethane. The organic layer was washed with aqueous solution of saturated sodium sulfate and dried over anhydrous sodium sulfate. After removing anhydrous sodium sulfate by filtration, the filtrate was concentrated under reduced pressure with a rotary evaporator. The residue was purified by silica gel column chromatography (45 g, n-hexane/ethyl acetate=1/1→1/3) to give 5-(4-acetoxyphenyl)-2-acetylamino-3-benzylpyrazine (c-33) as a pale yellow solid (355 mg, 57.8%). Rf=0.17 (n-hexane/ethyl acetate=1/1). Mp. 215.5-217° C. (dec.). UV (MeOH) λmax (log ε) 317 (4.09), 290 (4.08), 259 (4.15). UV (pH 7.4 PB) λmax (log ε) 315 (4.07), 292 (3.98), 253.5 (4.08). 1H NMR (400 MHz, DMSO-d6) δ 2.05 (s, 3H), 2.29 (s, 3H), 4.18 (s, 2H), 7.15-7.22 (m, 3H), 7.23-7.29 (m, 4H), 8.09-8.14 (AA′BB′, 2H), 8.94 (s, 1H), 10.31 (s, 1H). 13C NMR (75.5 MHz, DMSO-d6) δ 20.9, 23.0, 39.9, 122.5 (2C), 126.3, 127.7 (2C), 128.3 (2C), 129.0 (2C), 133.2, 137.8, 138.2, 144.7, 147.3, 150.5, 151.6, 169.1, 169.2. IR (KBr, cm−1) 706, 916, 1016, 1159, 1223, 1260, 1369, 1450, 1497, 1545, 1578, 1670, 1751, 3279. HRMS (FAB+) m/z 362.1509 (M+H, C21H20N3O3 requires 362.1505).

後処理

  1. customthe reaction
  2. extractionextracted 3 times with dichloromethane
  3. washThe organic layer was washed with aqueous solution of saturated sodium sulfate
  4. dry with materialdried over anhydrous sodium sulfate
  5. customAfter removing anhydrous sodium sulfate
  6. filtrationby filtration
  7. concentrationthe filtrate was concentrated under reduced pressure with a rotary evaporator
  8. customThe residue was purified by silica gel column chromatography (45 g, n-hexane/ethyl acetate=1/1→1/3)

出典と根拠

ORDレコード
ord-fafc8bf8061d4c55b5ee7858df95cdd3
出典データセット
uspto-grants-2013_04
特許番号
US08431525B2

反応ノート

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