Photochemische Reaktionen. 33. Mitteilung. Die Photoisomerisierung von 3-Oxo-Δ1;4-Steroiden in Dioxanlösung Strukturaufklärung der Photoisomeren und Bestimmung der Umlagerungs-Sequenzen

The photo-induced formation of ketonic and phenolic isomers from O-acetyl-1-dehydro-testosterone ( 1a ) and from its 4-methyl homologue 1d in dioxane solution has been described earlier [8][9][13]. The present paper summarizes the findings which resulted in the course of further investigations, and which, in part, have been published in preliminary form [11][14] and in recent reviews [12]. This work includes the ultraviolet irradiation of dienone 1a , its 10α-stereoisomer 2a , and its 1-, 2- and 4-methyl homologues 1b – d . A series of rearrangements occurred in each case, as shown in Charts 2, 3, and 19.