PURPOSE: To produce the subject compound which is important as a key feedstock in chemical industry, through stabilized operations in high yield by using a specific catalyst obtained by ion-exchange method in the catalytic dehydrogenation of methanol in the absence of oxygen.

CONSTITUTION: A zinc oxide/zeolite catalyst, which is prepared by the ion- exchange method, is used to effect catalytic dehydrogenation of methanol in the absence of oxygen whereby the subject compound is produced. In the reaction, the catalyst temperature is usually 450 to 650°C, preferably 500 to 600°C. The methanol feed rate is suitably 0.1 to 10.0g/h per gram of the catalyst. Further, the methanol is preferably diluted with an inert gas such as nitrogen, methane and/or hydrogen. The catalyst is prepared by dipping zeolite in aqueous zinc salt and the zinc ion is adsorbed to the zeolite by the ion-exchange method and firing the zeolite so that zinc oxide is formed on the zeolite.