| Popis: |
The photochemical reaction of 1,1,4,4-tetramethyl-2,3-tetralindione, 1, with hydrogen donors, such as xanthene and aldehyde, in the liquid phase has been investigated. When xanthene was selected as the hydrogen donor, the main products were the “1,2-adduct,” photo-reduced α-keto alcohol, and 9,9′-bixanthenyl. The photolysis of 1 and an aldehyde gave the mixture of the “1,2-adduct” and the “1,4-adduct.” However, in the reaction with isobutyraldehyde another type of “1,2-adduct” was obtained, i.e., a combination product between the semidione radical and the isopropyl radical resulting from the decarbonylation of the isobutyryl radical, together with propene and carbon monoxide. The usual type of “1,2-adduct,” the “1,4-adduct,” and the photo-reduced product (α-keto alcohol) were the minor products in the reaction. It was also confirmed that the original “1,4-adduct” obtained from 1 and acetaldehyde rearranged photochemically to a different type of “1,2-adduct,” but no reverse rearrangement was observed under... |
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