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Manganese Catalysis in the Activation of Si-H and B-H Bonds and Synthesis of Degradable Poly(Silylether)S from Renewable Resources

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Manganese Catalysis in the Activation of Si-H and B-H Bonds and Synthesis of Degradable Poly(Silylether)S from Renewable Resources University of North Dakota UND Scholarly Commons Theses and Dissertations Theses, Dissertations, and Senior Projects January 2019 Manganese Catalysis In The Activation Of Si-H And B-H Bonds And Synthesis Of Degradable Poly(silylether)s From Renewable Resources Srikanth Vijjamarri Follow this and additional works at: https://commons.und.edu/theses Recommended Citation Vijjamarri, Srikanth, "Manganese Catalysis In The Activation Of Si-H And B-H Bonds And Synthesis Of Degradable Poly(silylether)s From Renewable Resources" (2019). Theses and Dissertations. 2872. https://commons.und.edu/theses/2872 This Dissertation is brought to you for free and open access by the Theses, Dissertations, and Senior Projects at UND Scholarly Commons. It has been accepted for inclusion in Theses and Dissertations by an authorized administrator of UND Scholarly Commons. For more information, please contact [email protected]. MANGANESE CATALYSIS IN THE ACTIVATION OF SI-H AND B-H BONDS AND SYNTHESIS OF DEGRADABLE POLY(SILYLETHER)S FROM RENEWABLE RESOURCES by Srikanth Vijjamarri Bachelor of Science, Osmania University, Hyderabad, India, 2009 Master of Science, Osmania University, Hyderabad, India, 2011 A Dissertation Submitted to the Graduate School of the University of North Dakota in partial fulfillment of the requirements for the degree of Doctor of Philosophy Grand Forks, North Dakota December 2019 PERMISSION Title MANGANESE CATALYSIS IN THE ACTIVATION OF SI-H AND B-H BONDS AND SYNTHESIS OF DEGRADABLE POLY(SILYLETHER)S FROM RENEWABLE RESOURCES Department Chemistry Degree Doctor of Philosophy In presenting this dissertation in partial fulfillment of the requirements for a graduate degree from the University of North Dakota, I agree that the library of this University shall make it freely available for inspection. I further agree that permission for extensive copying for scholarly purposes may be granted by the professor who supervised my dissertation work or, in his absence, by the chairperson of the department or the dean of the Graduate School. It is understood that any copying or publication or other use of this dissertation or part thereof for financial gain shall not be allowed without my written permission. It is also understood that due recognition shall be given to me and to the University of North Dakota in any scholarly use which may be made of any material in my dissertation. Srikanth Vijjamarri December 1st, 2019 iii TABLE OF CONTENTS LIST OF FIGURES ------------------------------------------------------------------------------------------ vii LIST OF TABLES -------------------------------------------------------------------------------------------- x LIST OF SCHEMES----------------------------------------------------------------------------------------- xi LIST OF ABBREVIATIONS ------------------------------------------------------------------------------ xii ABSTRACT ------------------------------------------------------------------------------------------------ xvii CHAPTER 1 --------------------------------------------------------------------------------------------------- 1 GENERAL INTRODUCTION ..................................................................................1 1.1 Furanic monomers ..........................................................................3 1.2 Isohexides .......................................................................................5 1.3 Silyl ethers and poly(silylether)s ....................................................8 1.3.1 General methods to synthesize silyl ethers --------------------- 8 1.3.1A. Hydrosilylation -------------------------------------------------- 8 1.3.1B. Protection of hydroxyl functional groups ------------------- 10 1.5. Objectives of the dissertation ......................................................17 1.6. Structure of the dissertation .........................................................17 CHAPTER 2 -------------------------------------------------------------------------------------------------- 19 DEHYDROGENATIVE COUPLING OF ALCOHOLS AND CARBOXYLIC ACIDS WITH HYDROSILANES CATALYZED BY A SALEN Mn(V) COMPLEX ......19 2.1. Introduction .................................................................................19 2.2. Results and discussion .................................................................20 2.2.1. Dehydrogenative coupling of alcohols and silanes: Screening ------------------------------------------------------------------------------ 20 2.2.2. Alcohol substrate scope ----------------------------------------- 23 2.2.3. Dehydrogenative coupling of carboxylic acids and silanes 29 2.3. Mechanistic consideration ...........................................................30 iv 2.4. Conclusions .................................................................................31 2.5. Experimental section ...................................................................31 CHAPTER 3 -------------------------------------------------------------------------------------------------- 40 VERSATILE MANGANESE CATALYSIS FOR THE SYNTHESIS OF POLYSILYLETHERS FROM DIOLS AND DICARBONYLS WITH HYDROSILANES ..................................................................................................................................40 3.1. Introduction .................................................................................40 3.2 Results and discussion ..................................................................43 3.2.1. Optimization reactions ------------------------------------------- 43 3.2.2. Step-growth polymerization ------------------------------------ 47 3.2.3. Substrate scope: Diols ------------------------------------------- 48 3.2.4. Substrate scope: Dicarbonyls ----------------------------------- 50 3.2.5. Substrates with mixed functional groups --------------------- 52 3.3 Conclusions ..................................................................................55 3.4. Experimental section ...................................................................55 CHAPTER 4 -------------------------------------------------------------------------------------------------- 61 POLYMERS FROM BIO-DERIVED RESOURCES: SYNTHESIS OF POLY(SILYLETHER)S FROM FURAN DERIVATIVES CATALYZED BY A SALEN– Mn(V) COMPLEX...................................................................................................61 4.1 Introduction ..................................................................................61 4.2 Results and discussion ..................................................................63 4.2.1 Reactions between BHMF with hydrosilanes ----------------- 63 4.2.2 Substrate scope ---------------------------------------------------- 67 4.2.3 Thermal properties of PSEs -------------------------------------- 69 4.2.4 Degradation studies ----------------------------------------------- 72 4.3. Conclusions .................................................................................73 4.4. Experimental section ...................................................................74 v CHAPTER 5 -------------------------------------------------------------------------------------------------- 78 RENEWABLE ISOHEXIDES-BASED, HYDROLYTICALLY DEGRADABLE POLY(SILYLETHER)S WITH HIGH THERMAL STABILITY ..........................78 5.1 Introduction ..................................................................................78 5.2 Results and discussion ..................................................................81 5.2.1 Synthesis of PSEs from isosorbide and isomannide at extended reaction times ------------------------------------------------- 84 5.2.3. Hydrolytic degradation ------------------------------------------ 91 5.3. Conclusions .................................................................................94 5.4. Experimental section ...................................................................95 CHAPTER 6 ------------------------------------------------------------------------------------------------ 100 HYDROBORATION OF CARBONYLS BY A MANGANESE CATALYST ...100 6.1. Introduction ...............................................................................100 6.2. Results and discussion ...............................................................101 6.2.1. Hydroboration of ketones ------------------------------------- 103 6.2.2. Hydroboration of aldehydes ---------------------------------- 106 6.2.3. Chemoselective reactions ------------------------------------- 109 6.2.4. Mechanistic investigations ------------------------------------ 111 6.3. Conclusions ...............................................................................115 6.4. Experimental section .................................................................116 REFERENCES --------------------------------------------------------------------------------------------- 124 vi LIST OF FIGURES Figure Page , Figure 1. Distribution of types of natural products in biomass. ..................................................... 3 Figure 2. A general reaction scheme to produce HMF from cellulose ........................................... 4 Figure 3. Structure of 5-hydroxymethylfurfural and possible derivatives ...................................... 5 Figure 4. Isomers of isohexides and their structures....................................................................... 6 Figure 5. Schematic synthetic pathway of isohexides production from carbohydrates .................. 7 Figure 6. Hydrosilylation of unsaturated organic substrates
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