The 5-endo-trig-type cyclization has been performed using a Pd-bis(isoxazoline) catalyst. The present cyclization of β,γ-unsaturated carbonyl compounds gave γ-butenolides and 3-pyrrolin-2-ones in good to excellent yields.

This account focuses our works on the development of chiral spiro ligands bearing N-heterocycles as metalcoordinating units and their applications in the metal-catalyzed asymmetric reactions. The spiro bis(isoxazoline) ligands (SPRIXs), spiro bis(isoxazole) ligands, and spiro (isoxazoleisoxazoline) ligands were readily synthesized through intramolecular double nitrile oxide cycloaddition of the corresponding dioximes as a key step. An unprecedented activation of olefins was displayed by the Pd II complexes of these chiral spiro ligands in the enantioselective oxidative cyclizations, for example; the asymmetric tandem cyclization of dialkenyl alcohol via oxy-palladation produced a bicyclic ether in excellent enantioselectivity and enantioselective version of the aminocarbonylation proceeded for the first time.Other hitherto known chiral ligands we examined failed to promote these reactions.

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