A process for the preparation of methylheptanone and corresponding homologous methyl ketones involves the cross-aldolization of acetone with the corresponding aldehyde. The polar catalyst phase is introduced with acetone and an organic auxiliary solvent phase to form a two phase mixture in the presence of hydrogen. The corresponding aldehyde is then added at temperatures between 40° C. and 200° C. The process can be run in a continuous manner with the polar catalyst phase being recyled after regeneration. The use of the non-polar auxiliary solvent(s) increase yield and selectivity.