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Two approaches to the synthesis of an oxabicyclic pyrrolidine‐6‐one are described using enzymatic resolution and gold‐mediated catalysis as key steps toward enantiopure compounds previously reported as racemic mixtures. Addition of Grignard reagents to the ketone afforded a variety of diversified tertiary alcohols of interest for their reported pharmacological activities. [ABSTRACT FROM AUTHOR]

Efficient four- and five-step routes to access functionalized bicyclo[3.2.1]oct-2-ene and bicyclo[3.3.1]nonadiene via indium-mediated cycloisomerization of 1,6-enynes has been developed. This atom-economical catalytic process was optimized and relied on the efficiency of InCl3 leading to the preparation of functionalized bicyclic adducts in up to 99% isolated yield. The cyclization occurred on two different processes (5-exo versus 6-endo pathway) and were influenced by the substitution of the alkynyl moiety. The exo process was favored for non-substituted alkynes whereas the endo pathway was generally observed for substituted alkynes. Then, the presence of electron-withdrawing groups on the aryl substituted alkyne increased the ratio of the exo isomer. DFT calculations were performed on stability of intermediates and corroborated the intervention of InCl3. [ABSTRACT FROM AUTHOR]