Patent ID: 8410315

Claim:
A process for preparing olefinically unsaturated carbonyl compounds of the formula I where R 1 is hydrogen when R 2 is a radical of the formula II or R 1 and R 2 together are a radical of the formula III where R 3 , R 4 , R 5 and R 6 are each independently hydrogen, a C 1 -C 18 -alkyl group, an optionally substituted C 5 -C 18 -cycloalkyl group or an optionally substituted C 6 -C 18 -aryl group, and some of the ring atoms of the cycloalkyl and aryl groups are optionally replaced by heteroatoms selected from N, O and S, which comprises converting alcohols of the formula IV wherein R 1 , R 2 and R 3 are each as defined above, by oxidative dehydrogenation in an oxygenous atmosphere over a gold catalyst, which comprises using, as the gold catalyst, a supported catalyst which comprises gold or a mixture of gold and noble metals selected from Cu, Ag, Pd, Pt, Rh, Ru, W and Os, the conversion being performed at temperatures in the range from 50 to 240° C. and in the presence of air, hydrogen peroxide or a gas or gas mixture with an oxygen content in the range from 7 to 30% by volume as the oxygenous atmosphere and wherein the support material used is aluminum oxide, an aluminosilicate or a hydrotalcite or mixtures thereof.