Synthesis and photochemistry of 2,2-di-tert-butyl-6-(4,4-di-tert-butylbuta-1,3-dienyl)-2H-pyran

E,E-1,1,1,9,9-tetra-tert-butylnona-1,3,6,8-tetraen-5-one 7 undergoes cyclization under both basic and acidic conditions to yield 2,2-di-ter-butyl-6-(4,4-di-tert-butylbuta-1,3-dienyl)-2H-pyran 6. Upon photolysis of the 2H-pyran derivative ring opening to the ketone is observed. The 2H-pyran derivative is fluorescent and its fluorescene quantum yield and life time have been measured in cyclohexane and acetonitrile.