Verfahren zur Herstellung von alpha-substituierten Epoxid-Verbindungen

摘要

1381012 Preparation of α-substituted epoxides SNAM PROGETTI SpA 11 May 1972 [13 May 1971] 22235/72 Heading C2C α-Substituted epoxides of formula wherein X is a group selected from -COR4, -CN, -COOR4, phenyl, substituted phenyl and vinyl and R1 to R4, which may be the same or different, are hydrogen atoms or optionally substituted alkyl, cycloalkyl or aromatic radicals containing up to 12 C atoms, are prepared by oxidizing a #-substituted alcohol in the liquid phase and of formula with molecular oxygen in the presence of a CuI compound as catalyst. Preferred catalysts are compounds of the formulµ CuX1 and CuX1L n wherein X1 is Cl-, Br-, I-, F-, CN-, CH 3 OCO-, an enolate, NO 3 - or ClO 4 -, n is an integer from 1 to 6 and L is a co-ordinating base selected from unsubstituted or substituted phenanthrolines, dipyridyls, pyridines, dimethylsulphoxide, dimethylformamide, phosphines, arsines, stibines, imidazole and piperidine. The reaction, which is usually effected at 15-150‹ C. and 1-30 atmospheres absolute pressure, may be carried out in the presence of a solvent, other than the alcohol reactant, which is an optionally substituted aliphatic, cycloaliphatic, or aromatic hydrocarbon, an ether, or the co-ordinating base, L. The example describes the preparation of the epoxide wherein X is -CO-CH 3 , R1 and R2 are each -CH 3 and R3 is -H by the oxidation of 2-acetonyl-isopropanol.