1. Guillaume Barbe Guillaume Pelletier Miguel St-Onge Sébastien Vanier
Stereoselective Synthesis of Echinopines A and B
Guillaume Barbe Guillaume Pelletier Miguel St-Onge Sébastien Vanier
Lab B
Université de Montréal
May 13th 2008

2. Strategies for Ring Formation

3. Strategies for Ring Formation

4. Strategies for Ring Formation

5. Strategies for Ring Formation

6. Retrosynthetic Analysis

7. Asymmetric Synthesis of Norbornenone

8. Norbornenone Allylation

9. Norbornenone Allylation

10. Tandem Metathesis Key Step

11. Tandem Metathesis Key Step

12. Tandem Metathesis Key Step

13. Tandem Metathesis Key Step

14. Tandem Metathesis Key Step

15. Tandem Metathesis Key Step

16. Tandem Metathesis Key Step

17. Tandem Metathesis Key Step

18. Tandem Metathesis Key Step

19. Alkyne Formation

20. Alkyne Formation

21. Alkyne Formation

22. 7-exo-trig Radical Cyclization

23. 7-exo-trig Radical Cyclization

24. 7-exo-trig Radical Cyclization: Mechanism

25. 7-exo-trig Radical Cyclization: Mechanism

26. Allylic Alcohol Synthesis

27. Allylic Alcohol Synthesis

28. Chemoselective Cyclopropanation

29. Chemoselective Cyclopropanation

30. Conclusion
17 steps stereoselective synthesis
Features tandem metathesis and radical cyclization as key steps
Only one protecting group (acetal)
Late incorporation of cyclopropane (stability)