Abstract: The invention concerns a new process for the preparation of ketones; according to this process ketones are prepared from aldehydes and unsaturated compounds in the presence of bases using quaternary ammonium salts as catalysts.

Abstract: Ketones are prepared by reacting an aromatic or heterocyclic aldehyde in the presence of a cyanide ion with an unsaturated compound having the formula (I): ##STR1## wherein R.sup.1, R.sup.2 and R.sup.3 are the same or different and are selected from the group of hydrogen, optionally substituted aliphatic, cycloaliphatic, araliphatic, aromatic, heterocyclic and carboxylic acid ester andR.sup.4 is nitrile (CN), --CO--R.sup.5 or --CO--OR.sup.5whereinR.sup.5 is selected from the group of optionally substituted aliphatic, cycloaliphatic, araliphatic, aromatic and heterocyclic andR.sup.1 and R.sup.2 and/or R.sup.1 and R.sup.3 and/or R.sup.2 and R.sup.5 or R.sup.3 and R.sup.5 together with the carbon atoms to which they are attached as substituents may also form a carbocyclic or heterocyclic ring.Ketones prepared according to the process of the invention have the formula: ##STR2## wherein R.sup.1 .sup.' and R.sup.3 .sup.