Diastereodifferentiating isomerization

In relation to this, it is interesting to refer to the intramolecularly photosensitized diastereodifferentiating isomerization of 3-, 4-, and 5-benzoyloxycyclooctet-enes 66Z-68Z (Scheme 10) [51]. In particular, the de of photoproduct 66E is a critical function of substrate concentration (Fig. 6), leading to a switching of the diastereoselectivity at 10 mM. This apparently unusual phenomenon is reasonably... 

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