Process for preparing 5-ethylidene-2-norbornene of high quality

Abstract From the Canadian patent

5 Ethylidene-2-norbornene of high quality is effectively prepared by the isomerization of 5-vinyl-2norbornene containing 1 ppm to 0.5% by weight of 4-vinylcyclohexene in the presence of a catalyst selected from a solid base catalyst which is prepared by reacting alumina an alkali metal hydroxide and an alkali metal at a temperature in the range of 200 to 500°C; and a solid base catalyst which is prepared by reacting a water-containing alumina and an alkali metal in an amount that exceeds the molar equivalent of the water contained in the alumina at a temperature in the range between the melting point of the alkali metal and about 500°C in an inert gas atmosphere. When the …