Pentacyclo[4,4,0,02,100,3,5,04,8]decane and tetracyclo[4,4,0,02,10,04,8]decane

The 2,4,6,9- tetradehydroadamantane (pentacyclo[4,4,0,02,1003,5,04,8]decane)(III), formed by thermolysis of adamantane-2,6-diaone bis(tosylhydrazone)(II), gives upon catalytic hydrogenation tetracyclo[4,4,0,02,10,04,8]decane (VI) as the main product.