Abstract: The compounds are (+)- and (−)-2-cyclododecylpropanol and (+)- and (−)-2-cyclododecylpropionic acid, and salts thereof. (−)-2-cyclododecylpropanol is suitable as a fragrance while the virtually odorless (+) enantiomer is suitable as a fixative for other fragrances. The two enantiomers of 2-cyclododecylpropanol are prepared by reduction of the acid function of the enantiomers of 2-cyclododecylpropionic acid.

Abstract: The process for the preparation of carbonyl compounds of the formula I where R1 and R2 are a hydrocarbon radical, or R1 and R2 together are an unsubstituted or substituted alkylene group, and X is ═O or two alkoxy groups, comprises oxidizing alcohols of the formula II  where R1 to R2 and X are as defined above, with oxygen in the gaseous phase a) at temperatures of from 270 to 600° C. on silver coated catalysts which comprise an abrasion-resistant coating of metallic silver on a core of inert support material, or b) at temperatures of from 450 to 750° C. on silver crystals and/or copper crystals having a particle size of from 0.1 to 2.5 mm for a residence time of at most 0.1 second. Also claimed is an advantageous overall process for the preparation of &agr;-diketones, preferably diacetal, from the corresponding ketone, in particular methyl ethyl ketone, via the carbonyl compounds of the formula I where X is two alkoxy groups.

Abstract: The process for the preparation of carbonyl compounds of the formula I where R1 and R2 are a hydrocarbon radical, or R1 and R2 together are an unsubstituted or substituted alkylene group, and X is=O or two alkoxy groups, comprises oxidizing alcohols of the formula II where R1 to R2 and X are as defined above, with oxygen in the gaseous phase a) at temperatures of from 270 to 600° C. on silver coated catalysts which comprise an abrasion-resistant coating of metallic silver on a core of inert support material, or b) at temperatures of from 450 to 750° C. on silver crystals and/or copper crystals having a particle size of from 0.1 to 2.5 mm for a residence time of at most 0.1 second. Also claimed is an advantageous overall process for the preparation of &agr;-diketones, preferably diacetal, from the corresponding ketone, in particular methyl ethyl ketone, via the carbonyl compounds of the formula I where X is two alkoxy groups.

Abstract: 3-Hydroxy-.alpha.-cyclocitral derivatives of the general formula I ##STR1## where R.sup.1 is ##STR2## wherein R.sup.2 and R.sup.3 can be identical or different and are each straight-chain or branched alkyl of 1 to 6 carbon atoms, or R.sup.2 and R.sup.3 together form an ethylene or propylene group which can be substituted by methyl or ethyl, processes for their preparation and their use for the preparation of safranal and 3-hydroxy-.beta.-cyclocitral, as well as optically active - cyclocitral derivatives of the general formulae A and B ##STR3## where R.sup.1 is ##STR4## if X is hydrogen and Y is OH, but is otherwise ##STR5## where R.sup.2 and R.sup.3 have the above meanings, and X and Y together are oxygen, or X is hydrogen if Y is OH, and a process for the preparation of optically active 3-oxo-.alpha.-cyclocitral acetals, wherein a mixture of the corresponding racemic 3-oxo-.alpha.-cyclocitral acetals is separated into the optically active compounds by chromatography over a suitable chiral adsorbent.