for the following products
2,6-di-tert-Butyl-4-benzylidene-cyclohexa-2,5-dienone | 4-Benzylidene-2,6-di-tert-butyl-2,5-cyclohexadien-1-one | 4-Benzylidene-2,6-di-tert-butylcyclohexa-2,5-dienone and 2,6-bis-(1,1-Dimethylethyl)-4-(phenylmethylene)-2,5-cyclohexadien-1-one
