Part I: The photorearrangement of 1,3,3,4,5,6,-hexamethylbicyclo (2.2.2) oct-5-ene-2,7- and -2,8-dione. Part II: The synthesis and low temperature NMR spectrum of 1,4-diethyl-2,3,5,6,7,8,-hexamethylnapthalene