PURPOSE: To obtain the titled substance which is an intermediate for a compound having the insecticidial and antifungal activity easily in high yield, by reacting a halogenated tropone compound with an ethylene, etc. in the presence of a tetrakistriphenylphosphine palladium as a catalyst.

CONSTITUTION: A halogenated tropone compound, e.g. 2-chlorotropone or 3-iodotropone, is reacted with an ethylene or styrene in the presence of an amine and a tetrakistriphenylphosphine palladium or/and bisbenzylideneacetone palldium as a catalyst to give the aimed compound. The amount of the amine to be used in the reaction is two or more molar equivalents, and the amount of the catalyst to be used is 2W10mol%, preferably about 5mol%. An inert organic solvent, e.g. toluene or tetrahydrofuran, is used as a solvent to be used, and the reaction temperature is room temperature W about 150°C.