Herein we describe a rhodium-catalyzed enantioselective isomerization of meso-oxabicyclic alkenes to 1,2-naphthalene oxides. These potentially useful building blocks can be accessed in moderate to excellent yields with impressive enantioselectivities. Additionally, experimental findings supported by preliminary computations suggest that ring-opening reactions of bridgehead disubstituted oxabicyclic alkenes proceed through the intermediacy of these epoxides and may point to a kinetically and thermodynamically favored reductive elimination as the origin for the observed enantioselectivities.

While desymmetrizations by intermolecular asymmetric ring-opening reactions of oxabicyclic alkenes with various nucleophiles have been reported over the past two decades, the demonstration of an intramolecular variant is unknown. Reported herein is the first rhodium-catalyzed asymmetric cycloisomerization of meso-oxabicyclic alkenes tethered to bridgehead nucleophiles, thus providing access to tricyclic scaffolds through a myriad of enantioselective C-O, C-N, and C-C bond formations. Moreover, we also demonstrate a unique parallel kinetic resolution, whereby racemic oxabicycles bearing two different bridgehead nucleophiles can be resolved enantioselectively.

Herein we describe ar hodium-catalyzed enantioselective isomerization of meso-oxabicyclic alkenes to 1,2naphthalene oxides.T hese potentially useful building blocks can be accessed in moderate to excellent yields with impressive enantioselectivities.A dditionally,e xperimental findings supported by preliminary computations suggest that ring-opening reactions of bridgehead disubstituted oxabicyclic alkenes proceed through the intermediacy of these epoxides and may point to akinetically and thermodynamically favored reductive elimination as the origin for the observed enantioselectivities.Scheme 1. Developmentofthe rhodium-catalyzed enantioselective isomerizationo fmeso-oxabicycles.Supportinginformation and the ORCID identification number(s) for the author(s) of this article can be found under: http://dx.

While desymmetrizations by intermolecular asymmetric ring‐opening reactions of oxabicyclic alkenes with various nucleophiles have been reported over the past two decades, the demonstration of an intramolecular variant is unknown. Reported herein is the first rhodium‐catalyzed asymmetric cycloisomerization of meso‐oxabicyclic alkenes tethered to bridgehead nucleophiles, thus providing access to tricyclic scaffolds through a myriad of enantioselective C−O, C−N, and C−C bond formations. Moreover, we also demonstrate a unique parallel kinetic resolution, whereby racemic oxabicycles bearing two different bridgehead nucleophiles can be resolved enantioselectively.