Photoexcited nitrobenzene for benzylic hydroxylation: the synthesis of 17β-acetoxy-9α-hydroxy-3-methoxy-estra-1,3,5(10)-triene

A novel method for benzylic hydroxylation is introduced based on the use of photo-excited nitrobenzene. Applying this method 17β-acetoxy-3-methoxy-estra-1,3,5(10)-triene (I) is efficiently converted to 17β-acetoxy-9α-hydroxy-3-methoxy-estra-1,3,5(10)-triene (IIIa).