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.

The cross-coupling of maleimides with electron-deficient alkenes such as acrylates proceeds smoothly under ruthenium catalysis. This unique C-C coupling provides a simple, straightforward synthetic method for preparing alkylidene succinimide derivatives.

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Die Umsetzung von Dicyclopentadienyl‐isoprenyl‐zirkonium (1) mit den Carbonsäureestern (H) liefert ein Gemisch der isomeren Butenylketone (III) und (IV) in sehr hohen Ausbeuten.

The cis‐isoprene zirconium complex (I) reacts with the unsaturated ketones (II) and esters (V), forming a C‐C bond between the first atom of the isoprene moiety and the carbonyl group.