Hydrochloric Acid → 2-t-Butyldimethylsilyl-3-formyl-6-methoxybenzofuran

HRID 218821노트

반응식

HRID 218821 반응식
[Si:1]([CH:8]1[C:12](=[CH:13][O:14][Si](C(C)(C)C)(C)C)[C:11]2[CH:22]=[CH:23][C:24]([O:26][CH3:27])=[CH:25][C:10]=2[O:9]1)([C:4]([CH3:7])([CH3:6])[CH3:5])([CH3:3])[CH3:2].Cl>CO>[Si:1]([C:8]1[O:9][C:10]2[CH:25]=[C:24]([O:26][CH3:27])[CH:23]=[CH:22][C:11]=2[C:12]=1[CH:13]=[O:14])([C:4]([CH3:7])([CH3:6])[CH3:5])([CH3:2])[CH3:3]

참가 물질

4

반응물 2

HCID 313Hydrochloric AcidHCID 672878412-t-Butyldimethylsilyl-3-(t-butyldimethylsilyloxymethylene)-6-methoxy-benzofuran

생성물 1

HCID 574219572-t-Butyldimethylsilyl-3-formyl-6-methoxybenzofuran

시약·촉매·용매 1

HCID 887Methanol용매

실험 절차

To a solution of 2-t-butyldimethylsilyl-3-(t-butyldimethylsilyloxymethylene)-6-methoxy-benzofuran (1.09 g, 2.69 mmol) in methanol (100 mL) was added concentrated hydrochloric acid (200 μL) and the reaction was stirred for 30 minutes (monitored by tlc), quenched with triethylamine (2 mL) and the solvent removed by distillation under vacuum. The residue was dissolved in dichloromethane (20 mL), washed with water (10 mL), dried over magnesium sulfate, concentrated under vacuum and co-distilled with toluene (20 mL); 1H NMR (300 MHz, CDCl3) δ 7.57(d, 1H, J=8.57 Hz), 7.00(d, 1H, J=2.17 Hz), 6.86(dd, 1H, J=8.55, 2.22 Hz), 4.81(s, 2H, CH2), 3.84(s, 3H, OMe), 0.94(s, 9H), 0.37(s, 6H). The crude yellow paste (˜985 mg) was dissolved in dry dichloromethane (4 mL) and added to a stirred solution of Collin's reagent (chromium trioxide (1.01 g), pyridine (1.65 mL) in dry dichloromethane (30 mL)). The suspension was stirred for 10 minutes, filtered and the residue washed with diethyl ether (20 mL). The filtrate was concentrated onto silica (10 g) and purified by flash chromatography (silica gel, eluent=hexane/diethyl-ether/triethylamine (90:9:1) to afford the title compound as a light yellow oil which crystallized on standing (485 mg, 68%); 1H NMR (300 MHz, CDCl3) δ 10.25(s, 1H, CHO), 8.06(d, 1H, J=8.61 Hz), 7.03(d, 1H, J=2.16 Hz), 6.95(dd, 1H, J=8.60, 2.19 Hz), 3.84(s, 3H, OMe), 0.97(s, 9H), 0.46(s, 6H); 13C NMR (75 MHz, CDCl3) δ 186.91(CHO), 174.18, 159.19, 159.17, 132.82, 122.77, 117.34, 113.56, 95.36, 55.60, 27.04, 17.09, −5.24.

후처리

  1. customquenched with triethylamine (2 mL)
  2. customthe solvent removed by distillation under vacuum
  3. dissolutionThe residue was dissolved in dichloromethane (20 mL)
  4. washwashed with water (10 mL)
  5. dry with materialdried over magnesium sulfate
  6. concentrationconcentrated under vacuum and co-distilled with toluene (20 mL)
  7. dissolutionThe crude yellow paste (˜985 mg) was dissolved in dry dichloromethane (4 mL)
  8. additionadded to a stirred solution of Collin's reagent (chromium trioxide (1.01 g), pyridine (1.65 mL) in dry dichloromethane (30 mL))
  9. stirringThe suspension was stirred for 10 minutes
  10. filtrationfiltered
  11. washthe residue washed with diethyl ether (20 mL)
  12. concentrationThe filtrate was concentrated onto silica (10 g)
  13. custompurified by flash chromatography (silica gel, eluent=hexane/diethyl-ether/triethylamine (90:9:1)

출처 및 근거

ORD 기록
ord-77f8f20b38ec483bbfd61bbb8a75fe60
출처 데이터셋
uspto-grants-2012_06
특허 번호
US08198466B2

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