Hydrogen Peroxide → 1-Phenyl-7-oxabicyclo[4.1.0]heptane

Beteiligte Stoffe

Reaktionsschritte

In a 50 mL flask equipped with a magnetic stirrer, 7.9 g (50 mmol) of 1-phenylcyclohexene and 63 mg (0.25 mmol, 0.5 mol %) of MTO are dissolved in 1.5 Molar CH2Cl2 and to this solution is added 0.48 mL (6 mmol, 12 mol %) of pyridine followed by 7.6 mL (75 mmol; 1.5 equivalents) of 30% aqueous H2O2 added dropwise from a syringe (circa 5-10 minutes). During the H2O2 -addition the temperature is kept at 20-25° C. by applying an external cooling bath. The reaction is complete after 6 h and the aqueous phase is seperated and discarded. The remaining H2O2 in the yellow organic phase is decomposed to O2 and H2O by stirring with a catalytic amount of MnO2 (circa 10 mg). After the yellow color has completely disappeared the mixture is dried over Na2SO4, concentrated, and purified by filtration through a short column of silica gel which has been deactivated with NEt3. The column is washed with hexane/CH2Cl2 and concentration of the eluate affords 7.9 g (91%) of 1-phenyl-1,2-epoxycyclohexane as a colorless oil.

Herkunft & Nachweise