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I. Progress Toward the Development of an Alkyl Heck Reaction II

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I. Progress Toward the Development of an Alkyl Heck Reaction II I. Progress Toward the Development of an Alkyl Heck Reaction II. Preparation of an Unusual Palladacycle Thesis Presented in Partial Fulfillment of the Requirements for the Degree Master of Science in the Graduate School of The Ohio State University By Jimmy Alvarez Graduate Program in Chemistry The Ohio State University 2010 Thesis Committee: Professor James P. Stambuli Professor Jovica Badjic Copyright by Jimmy Malery Alvarez 2010 Abstract Transition-metals have been an area of high interest in organic chemistry because of the myriad of chemical transformations they can achieve. The Heck reaction is an example of these tranformations and widely used in organic synthesis. But, it is limited because one can only use either aryl or alkenyl halides. The first topic that will be discussed in this thesis is the progress made toward developing an alkyl Heck reaction. The final goal was not achieved but a reductive alkylation on non-activated alkenes was accomplished. The second topic deals with an interesting new palladacycle. Palladacycles have many applications in organic and bio-organic chemistry. A few of their applications are as catalyst, pre- catalyst, chiral auxiliaries and as mesogenic and photoluminescent agents. Palladacycle A was tested to see if it was the catalytically active Pd species in reactions catalyzed by Pd(OAc)2 and P(t-Bu)3. It was found that palladacycle A was not the active catalyst but has potential as a pre- catalyst. The optimal conditions to afford palladacycle A were also established. ii Dedication To my family. iii Acknowledgments I would like to begin by thanking Professor James P. Stambuli, my advisor, for allowing me to work in his group during my graduate career at The Ohio State University. He has been a very good mentor; his up-front demeanor has helped me to mature as a chemist and a person. His vast knowledge in both inorganic and organic chemistry was always inspirational. James’ advice and guidance supported me through my project from the very beginning. His drive and ambition rub off on his students and helps us become better chemist. The research going on in the Stambuli lab is amazing and will only get better. I also would like to thank Professor Jovica Badjic for serving on my thesis committee. I would also like to thank the entire Stambuli group who. First, Dr. Nicolas Proust, thank you for answering so many questions and proofreading this thesis. A very special shout-out goes to William Henderson (Big 6), Sean Whittemore (Chankla), Chris Check (Baby Check) and Matt Lauer (Stambuli Rules), for all the unforgettable weekends at Baby Check’s and Big 6’s. It wouldn’t have been the same without you guys. Brenda and Kamala you can finally take the earmuffs off. Thanks for all the birthday cakes Brenda, the banana cheese cake is still the best. I would also like to mention the rest of our group members who were always willing to lend a helping hand: Chad, Matt V., Mathieu and Carla. Last but not least our undergrads Eric, Jen, and Zack. iv My final thanks go to my parent, little brother, and my best friends Tasha, Ronald and Antwyne, (I’m finally coming home) for everything they have done for me and always being behind me when I needed them. None of this would have been possible without you. v Vita September 8th 1985 ….......................................................Born – Los Angeles, California, USA May 2007...........................................................................B. S. Chemistry, Edinboro University of Pennsylvania, Edinboro, Pennsylvania August 2007- Present……………………………………..Graduate Teaching Assistant `The Ohio State University Publications Henderson, W.; Eichman, C.; Alvarez, J.; Gallucci, J.; Stambuli, J. “An Unusual Palladium(II) Complex from Palladium Acetate and Tri-tert-butyl Phosphine.” Organometallics, 2010, Manuscript in Preparation. Field of Study Major Field: Organic Chemistry vi Table of Contents Abstract ............................................................................................................................................ ii Dedication ....................................................................................................................................... iii Acknowledgments........................................................................................................................... iv Vita.................................................................................................................................................. vi List of Figures ................................................................................................................................. ix List of Tables ................................................................................................................................... x List of Schemes ............................................................................................................................... xi List of Abbreviations .................................................................................................................... xiii Chapter 1 ...................................................................................................................................... 1 1.1 Background .......................................................................................................................... 1 1.2 The Heck Reaction ............................................................................................................... 3 1.3 Palladacycle ......................................................................................................................... 6 Chapter 2 .................................................................................................................................... 10 2.1 Background Information .................................................................................................... 10 2.2 Synthesis of the Heck Product ........................................................................................... 11 2.3 Results and Discussion ...................................................................................................... 15 2.4 Ethereal Coordinating Alkenes .......................................................................................... 15 2.5 Pyridyl Coordinating Alkenes ............................................................................................ 19 2.6 Mechanistic Considerations ............................................................................................... 22 2.7 Solvent Selection ............................................................................................................... 25 2.8 Base Selection .................................................................................................................... 26 2.9 Phosphine Selection ........................................................................................................... 28 2.10 Further Optimization .......................................................................................................... 29 2.11 Conclusion ..................................................................................................................... 32 Chapter 3 .................................................................................................................................... 33 3.1 Background ........................................................................................................................ 33 vii 3.2 Results and Discussion ...................................................................................................... 34 3.3 Synthesis of Palladacycle A ............................................................................................... 34 3.4 Variable Temperature NMR Experiments ......................................................................... 37 3.5 Amination Reactions .......................................................................................................... 40 3.7 Conclusion ......................................................................................................................... 45 Chapter 4 .................................................................................................................................... 46 4.1 General Methods ................................................................................................................ 46 4.2 Chapter 2: Experimental Methods ..................................................................................... 47 4.3 Chapter 3: Experimental Methods ..................................................................................... 54 Appendix .................................................................................................................................... 56 Crystal Data ............................................................................................................................... 65 Bibliography .............................................................................................................................. 93 viii List of Figures 1.1 Palladacycle A .................................................................................................................... 7 1.2 Types of Palladacycles ........................................................................................................ 8 1.3 Palladacycle B ....................................................................................................................
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