| 摘要 |
The preparation of epoxides of the general formula I in which the substituents R1, R2, R3, R4, R5 are independently hydrogen, C1-C20-alkyl, C3-C12-cycloalkyl, C4-C20-cycloalkylalkyl, C1-C20-hydroxyalkyl, a heterocyclic ring, or an aryl or C7-C20-arylalkyl group optionally substituted by C1-C8-alkyl, C1-C8-alkoxy, halogen, C1-C4-haloalkyl, C1-C4-haloalkoxy, phenyl, phenoxy, halophenyl, halophenoxy, carboxy, C2-C8-alkoxycarbonyl, or cyano, or R1 and R2 or R1 and R3 or R1 and R4 or R3 and R4 or R4 and R5 together form a (CH2)n group in which n is an integer from 1 to 10 and which may be optionally substituted by C1-C8-alkyl, C1-C8-alkoxy, and/or halogen, and R6 is hydrogen, C1-C8-alkyl, or benzyl, is carried out by a procedure in which an allyl alcohol of the general formula II in which R1, R2, R3, R4, R5 have the meanings stated above, is either a) electrochemically oxidized in the presence of an auxiliary electrolyte or b) oxidized with a halogen at a pH ranging from 7.5 to 14, in both cases in the presence of an alkanol of the general formula III R6-OH(III),in which R6 has the meaning stated above.
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