Twice expanded: Substituted naphthols were prepared in a novel synthetic route starting from alkenyl benzocyclobutenol derivatives. The conversion includes two successive ring-enlargement processes (A→B→C; see scheme). The halonium ion (X+) induces expansion of the four-membered ring to a five-membered ring, and SmI2 promotes the expansion of the five-membered ring to the six-membered ring with concomitant elimination of ROSmI2.
If you can't find a tool you're looking for, please click the link at the top of the page to "Go to old article view". Alternatively, view our Knowledge Base articles for additional help. Your feedback is important to us, so please let us know if you have comments or ideas for improvement.