Nitronaphthalenes as Diels–Alder dienophiles

1-Nitronaphthalene, 2-nitronaphthalene and 1,3-dinitronaphthalene react with Danishefsky diene as normal electron demand Diels–Alder dienophiles to give hydroxyphenanthrene derivatives as principal products in reasonable yields. The aromatization is an expected behavior in thermal reactions involving nitro-substituted compounds. However, it was possible to isolate the primary cycloadducts when using 1,3-dinitronaphthalene, although in very low yields. Other less reactive dienes do not undergo cycloaddition.