No abstract

A Michael-aldol domino reaction sequence of acenaphthenequinone with acetophenone in the presence of KOH in methanol solvent leading to the formation of three different 2:2 adducts arising through three distinct reaction sequences is described. Similar sequences leading to a highly substituted furan derivative were observed in the reaction between phenanthrenequinone and acetophenone.

Irradiation of 3-methoxy-3-aryl-3H-1-oxacyclopenta[l]phenanthren-2-one derivatives 5a–d resulted in singlet-mediated decarbonylation reaction leading to the formation of phenanthrene derivatives 9a–d. The structure of the photoproduct was unequivocally established on the basis of X-ray crystallographic analysis.