Efficient Tetrahydropyranylation of Phenols and Alcohols Catalyzed by Supported Mo and W Keggin Heteropolyacids

References

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• The used catalysts, MPA and TPA both supported on silica, were prior to the reaction, washed with toluene three times during 24 h each, with continuous stirring. The final content of HPA showed to be 0.3 mg MPA(TPA)/mg of catalyst
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• Analytical data for selected acetals: 1—THP: Calcd. for C11H14O2: C, 74.13, H, 7.92. Found: C, 74.01, H, 7.90. 2—THP: Calcd. for C11H13NO4: C, 59.19, H, 5.87, N, 6.27. Found: C, 59.23, H, 5.85, N, 6.24. 4—THP: Calcd. for C12H16O3: C, 69.21, H, 7.74. Found: C, 69.16, H, 7.72. 5—THP: Calcd. for C15H22O2: C, 76.87, H, 9.48. Found: C, 76.81, H, 9.44. 8—THP: Calcd. for C15H16O2: C, 78.92, H, 7.06. Found: C, 78.87, H, 7.03. 10—THP: Calcd. for C13H18O2: C, 75.69, H, 8.80. Found: C, 75.62, H, 8.78. 11—THP: Calcd. for C14H20O2: C, 76.32, H, 9.15. Found: C, 76.25, H, 9.12. 13—THP: Calcd. for C13H18O3: C, 70.24, H, 8.16. Found: C, 70.19, H, 8.12
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