Enantioselective synthesis of (9R,10S)-dihydrosterculic acid : overcoming unanticipated challenges in α,β-unsaturated 1,1-Bis(sulfoxides) [thesis]

John Palko
Conform em ent a la loi canadienne sur la protection de la vie privee, quelques formulaires secondaires ont ete enleves de cette these. Bien que ces formulaires aient inclus dans la pagination, il n'y aura aucun contenu manquant. Canada Abstract A diastereoselective Corey-Chaykovsky cyclopropanation of 1,1-alkylidene bis(sulfoxides) is applied to enantioselective syntheses of natural products (9i?,105)dihydrosterculic acid (1) and methyl (9R, 105)-dihydrosterculate (2). The synthesis of 1 was
more » ... ynthesis of 1 was achieved in 16.1% yield over eight steps and the synthesis of 2 was achieved in 17.3% yield over seven steps, both prepared from commercially available 9-decen-l-ol. Featured in the main synthetic route is a regioselective C-S bond cleavage and alkylation sequence to construct the cis relationship of the cyclopropane ring and improved conditions for the hydrolysis of 2. Future work on this project includes the identification of cyclopropane desaturase from Sterculia and the determination of the cryptoregiochemicastry and stereoselectivity for the A9 desaturation of 1. I would first like to give much thanks and appreciation to Dr. Peter Buist for providing financial support for my graduate studies. Without his generosity I would not have been able to experience the life lessons and frustrations graduate school has taught me here at Carleton. I won the war after losing so many battles, sir. Next, I want to express my full respect and gratitude towards Dr. Jeffrey Manthorpe. 10% o f everything I learned as a scientific researcher was absorbed during many discussions and meetings we have had. The remaining 90% was spent reabsorbing the first 10% of everything many, many, many times over. I guess it has been the total opposite of getting two birds stoned at once. Thanks again for displaying endless patience with me and my antics over the years. Of course, I have to thank the many labmates I have worked with over the years. Special thanks go out to Monica Gill and Han Kong (a.k.a. Handouken, Handrum, Han the Zerg and many more) for many enjoying thoughtful and unthoughtful discussions, as well as all the long days and late nights working in the lab together. I want to take this sentence to apologize for all the times I have accidentally scared Monica and purposely scared Han in the lab and using it as my main source of entertainment. Thanks for being super patient while I spent too much time in group meeting picking apart your poster figures before printing. As a final thank you, I left extra space between your names in this section. Hopefully future-me will leave it uncorrected before this hits the printers. This paragraph goes out to the Palko fam jam (Mom, Dad, Nicholas Picholas,
doi:10.22215/etd/2012-06779 fatcat:iujfaywb7zhl5hs2m54oc22it4