Acetone → 5-Tert-butyloxazole-4-carboxaldehyde

HRID 887984Notes

Reaction equation

HRID 887984 reaction equation
[C:1]([C:5]1[O:9][CH:8]=[N:7][C:6]=1[CH:10]=C(O)C(O)=O)([CH3:4])([CH3:3])[CH3:2].CC(C)=[O:18]>O=[Mn]=O>[C:1]([C:5]1[O:9][CH:8]=[N:7][C:6]=1[CH:10]=[O:18])([CH3:2])([CH3:3])[CH3:4]

Participants

4

Reactant 2

HCID 180AcetoneHCID 665900433-(5-tert-Butyloxazol-4-yl)-2-hydroxyacrylic acid

Product 1

HCID 210314885-Tert-butyloxazole-4-carboxaldehyde

Reagents, catalysts & solvents 1

HCID 14801Manganese dioxideCatalyst

Procedure

To a solution of oxazole alcohol 3 (9.9 g, 64 mmol) in acetone (200 mL, Aldrich, Cat. No. 179124) was added MnO2 (27.7 g, 319 mmol, 5 equiv., Wako Pure Chemical, Osaka, Japan, Cat. No. 138-09675), and the mixture was stirred at room temperature overnight. After celite filtration to remove MnO2, the solvent was removed by evaporation, and the residual pale brown oil was dissolved in CHCl3 and applied to silica-gel column chromatography (prepared with CHCl3), then eluted with CHCl3:MeOH (100:1 to 50:1), to give an pale yellow oil of aldehyde 4 (5.54 g, 57% (38% in two steps)). Rf 0.65 (CHCl3:MeOH=10:0.5), 1H NMR (300 MHz CDCl3) δ 10.10 (s, 1H), 7.77 (s, 1H), 1.47 (s, 9H); HRMS (EI): m/z 153.0794 (M+) (Calcd for C8H11NO2: 153.0790).

Workup

  1. filtrationAfter celite filtration
  2. customto remove MnO2
  3. customthe solvent was removed by evaporation
  4. dissolutionthe residual pale brown oil was dissolved in CHCl3
  5. customapplied to silica-gel column chromatography (prepared with CHCl3)
  6. washeluted with CHCl3:MeOH (100:1 to 50:1)

Sources & evidence

ORD record
ord-2687baf00adb409880f746db88e42747
Source dataset
uspto-grants-2012_08
Patent number
US08247552B2

Reaction notes

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