PURPOSE: To obtain selectively compounds useful for raw materials of perfumes, solvents, pharmaceutical preparations, polymers or the like in a high yield by dehydrogenating diols by passing them in liquid phase over a catalyst containing copper and chromium and then passing the reaction mixture in gas phase over the catalyst to dehydrogenate.

CONSTITUTION: By dehydrogenating 3-10C diols (e.g. butandiol-1,4 or the like) by using a Cu/Cr catalyst containing 42% by weight Cu stabilized by 8% by weight BaO, and 40% by weight Cr in a first process in which the diols are passed in the liquid phase over catalyst from the lower part to the upper part of a solid phase reactor at 200°C, and subsequently thus obtained reaction mixture is further heated to a temperature of approximately 220°C and is passed in the gas phase from the upper part to the lower part of the solid phase reactor 230°C to dehydrogenate, and the aimed compounds comprising the corresponding lactone (e.g. γ-butylolactone or the like) useful for perfumes, solvents, pharmaceutical preparations, precursor for polymers or the like is provided.