| abstract |
Unsaturated ketones of the formula <IMAGE> and saturated ketones of the formula <IMAGE> where R1, R2 and R3 are each hydrogen, alkyl of 1 to 12 carbon atoms or a cycloalkyl, aryl, aralkyl or alkylaryl radical which inturn may be substituted, or R1 and R3 or R2 and R3, together with the carbon atoms to which they are bonded, may form a cycloalkane, are prepared by a process in which a 5-methylene-1,3-dioxolanone which is substituted in the 4-position and is of the forumla <IMAGE> where R1, R2 and R3 have the above meanings, (a) for the preparation of an unsaturated ketone, is converted in the presence of a zeolite, of a phosphate having a zeolite structure and/or of B, Ce, Fe, Zr or Sr phosphate as catalysts and (b) for the preparation of a saturated ketone, is converted in the presence of the same catalysts which additionally carry one or more hydrogenation components. |