The Rh-catalyzed hydroarylative and hydrovinylative cyclization of diynes with aryl ketones or enones gave monocyclic 1,3-dienes. Enynes also underwent the same reaction and chiral products were obtained with high ee using a chiral Rh catalyst. Carbonyl-directed activation of aromatic and vinylic C-H bonds is likely the initial step in the present transformation.

The enantioselective [2 + 2 + 2] cycloaddition of 1,6-diynes with alpha-methylene lactones and cyclic ketones gave various chiral spirocyclic compounds. The reaction proceeded with high enantioselectivity when the rhodium-xylylBINAP complex was used as a chiral catalyst. Not only exo-methylene cyclic compounds but also exo-methylene acyclic compounds could be used as coupling partners for diynes. The present protocol provides access to a new chiral library possessing a quaternary carbon center, including a spirocyclic system.

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H Bonds. -The reaction of diynes with aryl ketones or enones gives 1,3-dienes bearing pyrrolidine, cyclopentane or cyclohexane rings. The enantioselective reaction of enynes affords the products with high e.e. -(TSUCHIKAMA, K.; KUWATA, Y.; TAHARA, Y.-K.; YOSHINAMI, Y.; SHIBATA*, T.; Org. Lett. 9 (2007) 16, 3097-3099; Dep. Chem. Biochem., Waseda Univ., Shinjuku, Tokyo 169, Japan; Eng.) -R. Steudel 49-132