N-bromobutanimide → tert-Butyl (5-(bromomethyl)pyrazin-2-yl)carbamate

HRID 595901ノート

反応式

HRID 595901 の反応式
[CH3:1][C:2]1[N:3]=[CH:4][C:5]([NH:8][C:9](=[O:15])[O:10][C:11]([CH3:14])([CH3:13])[CH3:12])=[N:6][CH:7]=1.C1C(=O)N([Br:23])C(=O)C1>C(Cl)(Cl)(Cl)Cl>[Br:23][CH2:1][C:2]1[N:3]=[CH:4][C:5]([NH:8][C:9](=[O:15])[O:10][C:11]([CH3:12])([CH3:14])[CH3:13])=[N:6][CH:7]=1

参加物

4

反応物 2

HCID 67184N-bromobutanimideHCID 22046506tert-Butyl (5-methylpyrazin-2-yl)carbamate

生成物 1

HCID 45073740tert-Butyl (5-(bromomethyl)pyrazin-2-yl)carbamate

試薬・触媒・溶媒 1

HCID 5943Carbon Tetrachloride溶媒

反応条件

温度
85 °C

実験手順

A solution of tert-butyl 5-methylpyrazin-2-ylcarbamate (2.79 g, 13.33 mmol), NBS (2.61 g, 14.67 mmol) and AlBN (0.219 g, 1.33 mmol) in CCl4 (45 mL) was purged with Argon, then the solution was heated with 85° C. oil bath for 4 h. The reaction mixture was cooled to room temperature, concentrated and the residue was redissolved in EtOAc (˜50 mL), washed with dilute aqueous NaOH twice (10 mL 1 N NaOH diluted in 20 mL H2O), brine (30 mL), dried (Na2SO4) and concentrated. The residue was further purified by flash chromatography on silica gel eluted with gradient EtOAc/CH2Cl2 (0-30%) and tert-butyl 5-(bromomethyl)pyrazin-2-ylcarbamate was obtained in off-white solid. LCMS (m/z): 288.1/290.1 (MH+), 0.82 min; 1H NMR (400 MHz, CDCl3) δ ppm 9.26 (s, 1H), 8.32 (d, J=1.2 Hz, 1H), 7.62 (br. s., 1H), 4.56 (s, 2H), 1.56 (s, 9H).

後処理

  1. temperatureThe reaction mixture was cooled to room temperature
  2. concentrationconcentrated
  3. dissolutionthe residue was redissolved in EtOAc (˜50 mL)
  4. washwashed with dilute aqueous NaOH twice (10 mL 1 N NaOH diluted in 20 mL H2O), brine (30 mL)
  5. dry with materialdried (Na2SO4)
  6. concentrationconcentrated
  7. customThe residue was further purified by flash chromatography on silica gel
  8. washeluted with gradient EtOAc/CH2Cl2 (0-30%)

出典と根拠

ORDレコード
ord-4443b3e244824b1f9506d440f4c513ac
出典データセット
uspto-grants-2016_01
特許番号
US09242996B2

反応ノート

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