An enantioselective intramolecular oxidative cyclization of 4-alkenoic acids was developed. The reaction proceeded via a π-allyl Pd intermediate generated by an allylic C-H activation to give γ-lactone derivatives with moderate to good enantioselectivity. Spiro bis(isoxazoline) ligand, SPRIX, was indispensable for this asymmetric transformation.

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Enantioselective 6-endo-trig Wacker-Type Cyclization of 2-Geranylphenols: Application to a Facile Synthesis of (-)-Cordiachromene. -Palladium-catalyzed intramolecular oxidative Wacker-type cyclization of o-geranylphenols (I) predominantly provides access towards chromenes (II) via a 6-endo-trig pathway. The products are obtained in moderate yields and stereoselectivities. This method is applied to a direct protecting-group-free synthesis of cordiachromene (V), although stoichiometric amounts of Pd complex and ligand are necessary. -(TAKENAKA, K.; TANIGAKI, Y.; PATIL, M. L.; RAO, C. V. L.; TAKIZAWA, S.; SUZUKI, T.; SASAI*, H.; Tetrahedron: Asymmetry 21 (2010) 7, 767-770,

Enantioselective Cyclization of 4-Alkenoic Acids via an Oxidative Allylic C-H Esterification. -(TAKENAKA, K.; AKITA, M.; TANIGAKI, Y.; TAKIZAWA, S.; SASAI*, H.; Org. Lett. 13 (2011) 13, 3506-3509, http://dx.doi.org/10.1021/ol201314m ; Inst. Sci. Ind. Res., Osaka Univ., Ibaraki, Osaka 567, Japan; Eng.) -R. Steudel 45-091