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Catalytic Methods for Alkene Functionalization Reactions

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Catalytic Methods for Alkene Functionalization Reactions Iowa State University Capstones, Theses and Graduate Theses and Dissertations Dissertations 2019 Catalytic methods for alkene functionalization reactions Abhishek Ashok Kadam Iowa State University Follow this and additional works at: https://lib.dr.iastate.edu/etd Part of the Organic Chemistry Commons Recommended Citation Kadam, Abhishek Ashok, "Catalytic methods for alkene functionalization reactions" (2019). Graduate Theses and Dissertations. 17712. https://lib.dr.iastate.edu/etd/17712 This Dissertation is brought to you for free and open access by the Iowa State University Capstones, Theses and Dissertations at Iowa State University Digital Repository. It has been accepted for inclusion in Graduate Theses and Dissertations by an authorized administrator of Iowa State University Digital Repository. For more information, please contact [email protected]. Catalytic methods for alkene functionalization reactions by Abhishek Ashok Kadam A dissertation submitted to the graduate faculty in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY Major: Organic Chemistry Program of Study Committee: Levi M. Stanley, Major Professor George Kraus Aaron Sadow Arthur Winter Wenyu Huang The student author, whose presentation of the scholarship herein was approved by the program of study committee, is solely responsible for the content of this dissertation. The Graduate College will ensure this dissertation is globally accessible and will not permit alterations after a degree is conferred. Iowa State University Ames, Iowa 2019 Copyright © Abhishek Ashok Kadam, 2019. All rights reserved. ii Dedicated to my mother and father iii TABLE OF CONTENTS Page NOMENCLATURE ......................................................................................................... iv ACKNOWLEDGEMENTS ............................................................................................... vi ABSTRACT……………………………………………………………………… ........... ix CHAPTER 1. INTRODUCTION ....................................................................................... 1 CHAPTER 2. ENATIOSELECTIVE, PALLADIUM-CATALZYED CONJUGATE ADDITIONS OF ARYLBORONIC ACIDS TO b-ARYL, b,b-DISUBSTITUTED ENONES TO BIS-BENZYLIC QUATERNARY STEREOCENTERS .......................... 14 Abstract…………………………………………………………………………..14 Introduction………………………………………………………………………15 Results and Discussions………………………………………………………….17 Conclusion.………………………………………………………………………23 Experimental……………………………………………………………………..23 References………………………………………………………………………..50 CHAPTER 3. NICKEL-CATALYZED THREE-COMPONENT ALKENE CARBOACYLATION VIA ACTIVATION OF AMIDE C-N BONDS ......................... 53 Abstract…………………………………………………………………………..53 Introduction………………………………………………………………………54 Results and Discussions………………………………………………………….56 Conclusion……………………………………………………………………….66 Experimental……………………………………………………………………..66 References………………………………………………………………………..99 CHAPTER 4. PALLADIUM-CATALYZED, INTERMOLECULAR ACYLATIVE HECK REACTION USING AMIDES AS ACYL ELECTROPHILES ........................ 102 Abstract…………………………………………………………………………102 Introduction……………………………………………………………………..102 Results and Discussions………………………………………………………...107 Conclusions……………………………………………………………………..119 Experimental……………………………………………………………………120 References………………………………………………………………………129 CHAPTER 5. CONCLUSION ....................................................................................... 132 Summary………………………………………………………………………..132 Conclusions……………………………………………………………………..133 iv NOMENCLATURE Ar aryl equiv equivalent DCM dichloromethane THF tetrahydrofuran Et2O diethylether CPME cyclopentylmethylether COD 1,5-cyclooctadiene DMAP dimethylaminopyridine Et3N triethylamine DMSO dimethylsulfoxide DMF dimethylformamide EtOAc ethylacetate NMR Nuclear Magnetic Resonance HPLC High Performance Liquid Chromatography HRMS High Resolution Mass Spectrometry ESI Electrospray Ionization Pr propyl Bu butyl TLC Thin Layer Chromatography UV Ultra-violet h Hours ee enantiomeric excess v GC Gas Chromatography TFA trifluoroacetate MHz Megahertz dr diastereomeric ratio o ortho m meta p para sat saturated M molar mL milliliter calcd calculated cat catalyst vi ACKNOWLEDGMENTS I would like to take this opportunity to thank my advisor Prof. Levi Stanley for his constant support throughout my time here at Iowa State University. Levi, you have been a great role model. Your passion and dedication for science is truly inspiring. I look up to you for the professionalism with which you carry yourself. Thank you for always being patient and available for discussing problems, potential solutions, and new ideas. I have enjoyed talking about new ideas with you and getting feedback with constructive criticism. I would like to thank my committee members, Prof. George Kraus, Prof. Keith Woo, Prof. Aaron Sadow, Prof. Wenyu Haung, and Prof. Arthur Winter, for their advice over the years. I like to extend my gratitude to my advisor Prof. Levi Stanley, Prof. Aaron Sadow, and Prof. Wenyu Haung for writing recommendation letters for me. I am grateful to Drtina Chemistry Graduate Student Travel Award, GPSS Professional Development Grant (PAG) Award, and David N. and Minnie I. Wall Graduate Scholarship Award for their support. The journey of grad school has truly been a roller coaster ride where some times were scary and some full of thrill. I am thankful to all my family and friends for being there whenever I needed. To my mom and dad, thank you for being patient with me. I can barely start to imagine the struggle you must have gone through to first, give me the education I needed and then send me away to a different country. Dad, thank you for instilling in me the values of hard work and discipline. Mom, yes, I have had my lunch today! To my sister, thank you for being there always and taking care of mom and dad ever since I have been away from home. I can’t thank enough the three of you for your unconditional love and support. vii I consider myself lucky for having some incredible friends who have been very supportive and encouraging of my decisions. I would like to thank Aleem, Avipsa, Raghu, Naresh Anna, Shreyo, Mani, Pratik, Nitin, Abhijith, and Jani for being amazing seniors. I will cherish all the memories we have created together. Abhranil, thank you for being an awesome friend. Avipsa, thank you for your constant help and guidance when I first started out in the Stanley group. Aleem and Anna, thank you for all the delicious food you fed me! Raghu, thank you for being a great host during my first few days in Ames and a dear friend. I would like to express my gratitude to all my Stanley group collogues. Ryan, Tony, Kirsten, James, Sagarika, Tanner, Kevin, and Brian- you guys were a great bunch of people to work with. Tanner, I hope you enjoyed our arguments over the mechanism as much as I did! Thank you all for the help and discussion with the chemistry. Alex, Patrick, Haley, Hai, Kevin, Mason, Austin, Melisa- I look forward to all the amazing chemistry you guys will be putting out. Patrick and Melisa, I will cherish all our talks over (sometimes too many) long island ice teas at Café B. A major chunk of all my happy memories in Ames comes from spending time with all the awesome, cool, and talented musicians of PunkPunditz. Santhosh, Srikanth, Arpa, Amar, Soori, Jyothsna, Mehul, Anuraag, Amrit, Aishwarya, Yash, Neel, Debarpan, Akshay, Abhinav, and Sushain- we have created some awesome music together. I will be playing all these songs again and again for the rest of my life. A special thanks to my todd drive family, Shubhra, Yash, Neel, Jyothsna, Aishwarya, and Slesha, for all the food and movie nights! I would also like to thank Kruttika, Ashwini, Malvika, Amrit, Saurabh, and Harshil for all the fun trips and night-outs. viii A special shout out to my close friends, Ajinkya, Mallikarjun, Kaustubh, Nikhil, and Aditya, for being some of the best people in my life. Ajinkya and Mallik, thank you for visiting my place back home every now and then. My mom and dad thank you for revealing all my secrets! To Kaustubh, Nikhil, and Aditya- I hope we continue to explore more places around the world even if our lives get busier. I would like to thank Iowa State University and the Department of Chemistry at Iowa State University for making this a wonderful research experience. ix ABSTRACT This thesis presents the efforts towards developing transition metal-catalyzed protocols for rapid functionalization of alkenes. These protocols include – 1) enantioselective, palladium-catalyzed conjugate additions of arylboronic acids to generate compounds containing bis-benzylic quaternary stereocenter; 2) nickel-catalyzed three- component alkene carboacylation via activation of amide C-N bonds; 3) palladium- catalyzed intermolecular, acylative Heck reaction using amides as acyl electrophiles. Chapter II discusses a strategy to access cyclic ketones containing bis-benzylic quaternary stereocenters through enantioselective palladium-catalyzed conjugate additions of arylboronic acids to β-aryl β,β-disubstituted cyclic enones. The catalyst generated from palladium trifluoroacetate and a chiral, non-racemic (S)-4-tert-butyl-2-(2- pyridyl)oxazoline ligand allows conjugate addition of a wide range arylboronic acids to a variety of to β-aryl β,β-disubstituted cyclic enones to generate ketones containing bis- benzylic quaternary stereocenters in up to 92% yield and up to 93% ee. This protocol uses iterative addition strategy to minimize unproductive protodeboronation of arylboronic acid and leads to the formation
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