1. Asymmetric Benzoin Condensation Catalyzed by Chiral Rotaxanes Tethering a Thiazolium Salt Moiety via the Cooperation of the Component Reference Takata T. et al. Chem.Lett. 2000, 806-807 Takata T. et al. J.Am.Chem.Soc. 2004, 126, 3438-3439 Tobe Laboratory Hirokazu TAKANO

2. Structure of Rotaxane

3. Example of Rowan’s Rotaxane Catalyst the epoxidation of the axle by using the wheel component as catalyst. Thordarson, P.; Bijsterveld, E. J. A.; Rowan, A. E.; Nolte, R. J. M. Nature 2003, 424, 915. the first intramolecular rotaxane catalyst mimicking the DNA enzyme  -exonuclease.

4. Benzoin Condensation The cyanide ion-catalyzed

5. Benzoin Condensation Catalyst

6. Binaphthol-Based Chiral Crown Ether source of chiral environment

7. Synthesis of Pseudorotaxane Functionalized Chirality

8. The Face Selective Hydrogen Abstraction of 5 from 3

9. Rotaxane based on binaphthol-based crown ether 1 provides an effective chiral environment. Althrough the degree of chirality introduction is not high, this is the first example of asymmetric induction on rotaxane. Summary 1

10. Design of Rotaxane Catalysts Through -Space Through-Bond

11. Synthesis of Rotaxane 7a

12. Benzoin Condensation Catalized by Chiral Rotaxane ee = enantiomer excess ( エナンチオマー過剰率 )

13. Asymmetric Benzoin condensation catalyzed by 7 Concentlation of catalyst The length of the axle component Substituents on benzaldehydes Using DMSO as solvent Temperature effect Through-space Chirality Transfer

14. Synthesis of Rotaxane 10

15. Asymmetric Benzoin condensation catalyzed by 7, 10, 11 Influence of existance of ring component Through-bond Chirality Transfer

16. Summary 2 The authors’ first attempt to demonstrate the catalysis of rotaxanes may help clarify the fundamental features of rotaxane structure which was shown to give a unique reaction field in asymmetric benzoin condensation. A more precise design for the asymmetric rotaxane catalyst based on the guiding principle obtained here will result in rotaxanes with higher chemical and asymmetric yields.