反応 #324390

ord-5b05f4f9c146472f8b25f1d0747754b7

溶媒

反応条件

温度
50°CELSIUS
詳細条件
See reaction.notes.procedure_details.

後処理

  1. 1
    その他prepared above at 0° C.
  2. 2
    温度the mixture was heated
  3. 3
    温度After cooling to room temperature
  4. 4
    抽出the product was extracted with ethyl acetate (200 mL×3)
  5. 5
    抽出The combined organic extract
  6. 6
    洗浄was washed successively with water (200 mL) and brine (200 mL)
  7. 7
    乾燥by drying over anhydrous sodium sulfate
  8. 8
    ろ過After filtration and concentration under reduced pressure
  9. 9
    その他the residue was purified by column chromatography (silica gel 50 g, n-hexane/ethyl acetate=3/1)

実験手順

Under an argon atmosphere, to a mixture of 5-[4-(tert-butyldimethylsilyloxy)phenyl]-3-(thiophen-3-yl)pyrazin-2-amine (7g) (450 mg, 1.17 mmol) and 4-(dimethylamino)pyridine (15.5 mg, 127 μmol) dissolved in anhydrous pyridine (20 mL) was added 2-[4-(tert-butyldimethylsilyloxy)phenyl]acetyl chloride (10) prepared above at 0° C. and the mixture was heated with stirring at 50° C. for 15 hours. After cooling to room temperature, to this was added water and the product was extracted with ethyl acetate (200 mL×3). The combined organic extract was washed successively with water (200 mL) and brine (200 mL), followed by drying over anhydrous sodium sulfate. After filtration and concentration under reduced pressure, the residue was purified by column chromatography (silica gel 50 g, n-hexane/ethyl acetate=3/1) to give Compound 11g (512 mg, 809 μmol, 69.0%) as a yellow solid. Rf=0.22 (n-hexane/diethyl ether=2/3); 1H NMR (400 MHz, DMSO-d6) δ 0.16 (s, 6H), 0.20 (s, 6H), 0.92 (s, 9H), 0.94 (s, 9H), 3.56 (s, 2H), 6.72-6.82 (AA′BB′, 2H), 6.93-7.02 (AA′BB′, 2H), 7.12-7.22 (AA′BB′, 2H), 7.50 (dd, 1H, J=2.9, 5.0 Hz), 7.59 (d, 1H, J=5.0 Hz), 7.81 (d, 1H, J=2.9 Hz), 8.04-8.12 (AA′BB′, 2H), 8.91 (s, 1H), 10.50 (s, 1H); 13C NMR (75.5 MHz, DMSO-d6) δ −4.6 (4C), 17.90, 17.95, 25.50 (3C), 25.54 (3C), 41.9, 119.6 (2C), 120.3 (2C), 125.7, 126.0, 127.7, 127.9, 128.2 (2C), 128.8, 130.5 (2C), 137.1, 138.2, 142.0, 143.5, 148.0, 153.9, 156.8, 169.9; IR (KBr, cm−1) 517, 669, 712, 741, 781, 806, 839, 914, 1007, 1082, 1105, 1169, 1261, 1341, 1362, 1441, 1472, 1508, 1605, 1665, 2857, 2886, 2930, 2955, 3057, 3227; HRMS (ESI+) m/z 654.2618 ([M+Na]+, C34H45N3NaO3Si2+ requires 654.2612).

出典

DOI: 10.6084/m9.figshare.5104873.v1特許: US08642281B2uspto-grants-2014_02