Dimethylformamide → 2-Formyl-3-(4-methylphenyl)pyrrole

HRID 493162ノート

反応式

HRID 493162 の反応式
[CH3:1][C:2]1[CH:7]=[CH:6][C:5]([C:8]2[CH:12]=[CH:11][NH:10][CH:9]=2)=[CH:4][CH:3]=1.O=P(Cl)(Cl)Cl.CN([CH:21]=[O:22])C>C(Cl)Cl>[CH:21]([C:9]1[NH:10][CH:11]=[CH:12][C:8]=1[C:5]1[CH:4]=[CH:3][C:2]([CH3:1])=[CH:7][CH:6]=1)=[O:22]

参加物

5

反応物 3

HCID 6228DimethylformamideHCID 24813Phosphorus oxychlorideHCID 105349353-(4-Methylphenyl)pyrrole

生成物 1

HCID 467385812-Formyl-3-(4-methylphenyl)pyrrole

試薬・触媒・溶媒 1

HCID 6344Dichloromethane溶媒

実験手順

Following a standard procedure (Balasubramanian, T. et al., J. Org. Chem. 2000, 65, 7919-7929), a solution of 7 (472 mg, 3.00 mmol) in DMF (0.96 mL) and CH2Cl2 (30 mL) under argon was cooled to 0° C. and then POCl3 (340 μL, 3.60 mmol) was added dropwise. After 1 h, the flask was warmed to room temperature and stirred overnight (˜18 h). The reaction was quenched at 0° C. with 2.5 M NaOH (25 mL). The mixture was poured into water (50 mL), extracted with CH2Cl2, and the combined organic layers were washed with water, brine, dried (Na2SO4), and concentrated. The residue was chromatographed [silica, CH2Cl2/ethyl acetate (9:1)] to give a brown solid. 1H NMR spectroscopy showed two regioisomers in ˜13:1 ratio. Cooling of the solution (ethyl acetate/hexanes) at ˜−16° C. resulted in precipitation of an orange solid, which proved to be a single regioisomer (354 mg, 64%): mp 149-150° C.; 1H NMR δ 2.41 (s, 3H), 6.42-6.44 (m, 1H), 7.10-7.13 (m, 1H), 7.26 (d, J=8.0 Hz, 2H), 7.40 (d, J=8.0 Hz, 2H), 9.63-9.64 (m, 1H), 9.52-9.78 (br, 1H); 13C NMR δ 21.4, 111.6, 126.2, 128.9, 129.3, 129.7, 130.9, 137.7, 137.9, 180.2; FAB-MS obsd 186.0907, calcd 186.0919 (C12H11NO).

後処理

  1. customThe reaction was quenched at 0° C. with 2.5 M NaOH (25 mL)
  2. additionThe mixture was poured into water (50 mL)
  3. extractionextracted with CH2Cl2
  4. washthe combined organic layers were washed with water, brine
  5. dry with materialdried (Na2SO4)
  6. concentrationconcentrated
  7. customThe residue was chromatographed [silica, CH2Cl2/ethyl acetate (9:1)]
  8. customto give a brown solid
  9. customresulted in precipitation of an orange solid, which

出典と根拠

ORDレコード
ord-d43a9c3829334251a19b7a04d736ffc3
出典データセット
uspto-grants-2009_05
特許番号
US07534807B2

反応ノート

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