Session: Heterocycles & Aromatics:

Explored was the competitive ring-closing metathesis vs. ring-rearrangement metathesis of bicyclo[3.2.1]octenes prepared by a simple and convergent synthesis from bicyclic alkylidenemalono-nitriles and allylic electrophiles. It was uncovered that ring-closing metathesis occurs exclusively on the tetraene-variant, yielding unique, stereochemically and functionally rich polycyclic bridged frameworks, whereas the reduced version undergoes ring-rearrangement metathesis to 5–6–5 fused ring systems resembling the isoryanodane core. The ring-closing metathesis products also undergo an unexpected [3,3] sigmatropic rearrangement to yield cyclopenta-fused dihydrofurans or pyrroles.

Alexander Grenning

University of Florida

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