Catalytic Asymmetric Synthesis of Cage-type Organic Compounds by New Stereo-controlled Approach

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I reported an enantioselective ortho-lithiation of achiral paracyclophanes with oxygen atoms as directed moieties at both ends of ansa-chain using a chiral lithium reagent. The reaction of an unflippable 1,n-dioxa[n]paracyclophane (n?□11) with sec- utyllithium and (-)-sparteine gave the chiral mono-lithiated product. Additional amount of sec-butyllithium gave C_2-symmetric dilithiated product. The quenching of these lithium salts by appropriate electrophiles gave various planar-chiral aracyclophanes with excellent ee. The planar-chiral mono- and diphosphines, which were prepared by the above protocols, were used as chiral ligands in transition metal-catalyzed reactions.