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Enantioselectivity

Photochemistry. Enantioselectivity. Photochemistry. Chiral sensitizers Chiral auxiliaries Chiral complexing agents Solid-state photochemistry Circularly polarized light (CPL). Enantioselectivity. Y. Inoue, V. Ramamurthy (eds.) Chiral Photochemistry , Dekker, New York, 2004.

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Enantioselectivity

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  1. Photochemistry Enantioselectivity

  2. Photochemistry Chiral sensitizers Chiral auxiliaries Chiral complexing agents Solid-state photochemistry Circularly polarized light (CPL) Enantioselectivity Y. Inoue, V. Ramamurthy (eds.) Chiral Photochemistry, Dekker, New York, 2004

  3. Development of a chiral complexing agent (template) in the work group of Prof. Bach

  4. Principle of stereoselective photochemical reactions with template systems

  5. Scope of the Chiral Complexing Agent

  6. Enantioselective Catalysis – Chiral Multiplication A. Bauer, F. Westkämper, Nature2005, 436, 1139-1140.

  7. Table of Content Introduction Template Synthesis and [2+2] PCA in Solution (O) [2+2] PCA with Wang resin bounded Templates (O) [2+2] PCA with soluble Polymers (PEGs) (O) Continuous Flow System (O)

  8. Polymer-bound chiral templates in stereoselective photochemical reactions • Synthesis of a new Shield Precursor with a suitable linker for the Template System • Immobilisation of the Template on a Solid Support • Procedure for a heterogeneous enantioselective [2+2]-Photocycloaddition Reaction

  9. Glass Coil Metal Tube Metal Frit Development of a Continuous Flow Reactor Inlet (Starting Material) Outlet (Product)

  10. Template Synthesis – Variation of the Alkoxy Linker Position at the Backbone

  11. Template Synthesis – Variation of the Alkoxy Linker Position at the Backbone

  12. Template Synthesis – Variation of the Alkoxy Linker Position at the Backbone

  13. Template Synthesis – Variation of the Alkoxy Linker Position at the Backbone

  14. Synthesis of the Tetrahydronaphthoxazole Template

  15. Synthesis of the Tetrahydronaphthoxazole Template

  16. Synthesis of the Tetrahydronaphthoxazole Template

  17. Synthesis of the Tetrahydronaphthoxazole Template

  18. UV-Spectra of the Templates

  19. NMR Titration Experiments A. Bauer, T. Bach, Tetrahedron Asymmetry2004, 15, 3799-3803.

  20. 4-Allyloxy-2-chinolone as a test substrate

  21. 4-Allyloxy-2-quinolone as a test substrate

  22. Intramolecular [2+2] Photocycloaddition Reaction of 4-(Allyloxy)quinolin-2(1H)-one

  23. Intramolecular [2+2] Photocycloaddition Reaction of 4-(Allyloxy)quinolin-2(1H)-one

  24. Intramolecular [2+2] Photocycloaddition Reaction of 4-(Allyloxy)quinolin-2(1H)-one

  25. Intramolecular [2+2] Photocycloaddition Reaction of 4-(Allyloxy)quinolin-2(1H)-one

  26. Comparison between Standard and Rebek Template

  27. Comparison between Standard and Rebek Template

  28. Intramolecular [2+2] Photocycloaddition Reaction of 4-(Allyloxy)quinolin-2(1H)-one

  29. Kinetic Study of the [2+2] PCA of 4-(Allyloxy)quinolin-2(1H)-one in solution reaction conditions: -74 °C, l = 300 nm, toluene, 2.6 equiv. tetrahydronaphthoxazole → full conversion of the [2+2] PCA reaction in solution after 20 minutes

  30. Table of Content Introduction Template Synthesis and [2+2] PCA in Solution (O) [2+2] PCA with Wang resin bounded Templates (O) [2+2] PCA with soluble Polymers (PEGs) (O) Continuous Flow System (O)

  31. Immobilisation Experiments with the THNO-Template and Polystyrene derived Solid Supports

  32. Immobilisation Experiments with the THNO-Template and Polystyrene derived Solid Supports

  33. Immobilisation Experiments with the THNO-Template and Polystyrene derived Solid Supports

  34. Intramolecular [2+2] Photocycloaddition Reaction of 4-(Allyloxy)quinolin-2(1H)-one – Catalytic Cycle

  35. Intramolecular [2+2] Photocycloaddition Reaction of 4-(Allyloxy)quinolin-2(1H)-one – Studies on Penetration Depth average penetration depth ~0.19 mm → low conversion due to low transparency

  36. Immobilisation Experiments with the THNO-Template and Polyethylene Glycols (PEG)

  37. Immobilisation Experiments with the THNO-Template and Polyethylene Glycols (PEG)

  38. Intramolecular [2+2] Photocycloaddition Reaction of 4-(Allyloxy)quinolin-2(1H)-one – Catalytic Cycle

  39. Table of Content Introduction Template Synthesis and [2+2] PCA in Solution (O) [2+2] PCA with Wang resin bounded Templates (O) [2+2] PCA with soluble Polymers (PEGs) (O) Continuous Flow System (O)

  40. Continuous Flow System

  41. Continuous Flow System Reducing union with a metal frit (1/16 Inch " 1/4 Inch) 1/16 HPLC tubing 25 cm glass reactor

  42. Residence Time Distribution (RTD) Spectrum

  43. Residence Time Distribution (RTD) Spectrum

  44. Residence Time Distribution (RTD) Spectrum

  45. Continuous Flow System – Irradiation Experiments

  46. Continuous Flow System – Irradiation Experiments

  47. Vanessa Rodig (Trainee) Bach Workgroup Dr. Andreas Bauer (Continuous Flow Reactor)

  48. Imitation of a Continuous Flow Reactor (dye laser based on coumarin) Continuous Flow Reactor in Reality (N-Oxide-Rearrangement)

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