Process for preparing carbonyl compounds by catalysed oxidation of olefins and catalysts present microemulsions

A process for preparing a carbonyl compound of the formula ##STR4## by catalytic oxidation of an olefin of the formula ##STR5## where, in the formulae R.sup.1, R.sup.2 and R.sup.3 are, independently of one another, hydrogen;

• straight-chain or branched C.sub.1 -C.sub.8 -alkyl which is unsubstituted or monosubstituted or disubstituted by halogen, hydroxy, cyano, COO--C.sub.1 -C.sub.4 -alkyl, CO--C.sub.1 -C.sub.4 -alkyl, SO.sub.2 --O--C.sub.1 -C.sub.2 -alkyl or phenyl;
• or phenyl or naphthyl which are unsubstituted or monosubstituted or disubstituted by halogen, hydroxy, nitro, cyano, C.sub.1 -C.sub.4 -alkyl, COO--C.sub.1 -C.sub.4 -alkyl, CO--C.sub.1 -C.sub.4 -alkyl or SO.sub.2 --O--C.sub.1 -C.sub.4 -alkyl,
• and
• R.sup.1 and R.sup.3 or R.sup.2 and R.sup.3 can further more together form an alkylene chain .paren open-st.CH.sub.2 .paren close-st..sub.m where m=3-10 and 1-2 of the alkylene chain carbon atoms can be substituted by halogen, hydroxy, C.sub.1 -C.sub.4 -alkyl, COO--C.sub.1 -C.sub.4 -alkyl, CO--C.sub.1 -C.sub.4 -alkyl, SO.sub.2 --O--C.sub.1 -C.sub.4 -alkyl or phenyl,
• by an oxygen or oxygen-containing gas, wherein the oxidation is carried out at 0.degree.-200.degree. C. and 0.2-200 bar in the presence of a catalyst system comprising a palladium compound and one or more reoxidizing agents from the group of compounds of further subgroup metals and quinones, in a microemulsion as reaction medium and catalyst support, wherein the size of the droplets of said microemulsion range from 5 to 100 nm.