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(Bdeth2) and Its Metal Compounds University of Kentucky UKnowledge University of Kentucky Doctoral Dissertations Graduate School 2008 BENZENE-1,3-DIAMIDOETHANETHIOL (BDETH2) AND ITS METAL COMPOUNDS Kamruz Md Zaman University of Kentucky, [email protected] Right click to open a feedback form in a new tab to let us know how this document benefits ou.y Recommended Citation Zaman, Kamruz Md, "BENZENE-1,3-DIAMIDOETHANETHIOL (BDETH2) AND ITS METAL COMPOUNDS" (2008). University of Kentucky Doctoral Dissertations. 644. https://uknowledge.uky.edu/gradschool_diss/644 This Dissertation is brought to you for free and open access by the Graduate School at UKnowledge. It has been accepted for inclusion in University of Kentucky Doctoral Dissertations by an authorized administrator of UKnowledge. For more information, please contact [email protected]. ABSTRACT OF DISSERTATION Kamruz Md Zaman The Graduate School University of Kentucky 2008 BENZENE-1,3-DIAMIDOETHANETHIOL (BDETH2) AND ITS METAL COMPOUNDS _____________________________ ABSTRACT OF DISSERTATION _____________________________ A dissertation submitted in partial fulfillment of the requirement for the degree of Doctor of Philosophy in the College of Arts and Science at the University of Kentucky By Kamruz Md Zaman Lexington, Kentucky Director: Dr. David A. Atwood, Professor of Chemistry Lexington, Kentucky 2008 Copyright © Kamruz Md Zaman 2008 ABSTRACT OF DISSERTATION BENZENE-1,3-DIAMIDOETHANETHIOL (BDETH2) AND ITS METAL COMPOUNDS There is a global need to find a permanent and readily implemented solution to the problem of heavy metal pollution in aqueous environments. A dithiol compound, benzene-1,3-diamidoethanethiol (BDETH2), also known as N,N'-bis(2-mercaptoethyl) isophthalamide or N,N'-bis(2-mercaptoethyl)-1,3-benzenedicarboxamide, capable of binding divalent metal ions, has been synthesized and characterized. A broad range of BDET-metal compounds, spanning the periodic chart, has been prepared and characterized by IR, MS, EA, Raman, XAFS and TGA. The characteristics of the BDET-M compounds were determined through secondary reactions. In an effort to derivatize BDET-M compounds through alkylalumination a new cyclic compound, 1,3- bis(4,5-dihydrothiazolo)benzene, has been synthesized by refluxing BDETH2 in the presence of AlMe3. Mineral coating studies have been performed and it was found that coating with BDET prevents metal leaching. XPS studies indicated that covalent bonds exist between BDET and metals at the mineral surfaces. BDETH2 is not water soluble and must be used as an ethanolic solution to precipitate metals from water. In an effort to find similar ligands that are water-soluble another dithiol compound, N,N'-bis(2-mercaptoethyl)oxalamide (MOA), and a monothiol compound, N-mercaptoethyl-furoylamide (MFA), have been synthesized. Each was found to precipitate Cd, Hg and Pb from water, to varying degrees. Some metal compounds of MOA, MFA and dithiothreitol (DTT), a water- soluble dithiol compound have been prepared and characterized. These compounds provide insight into the properties of the BDET-M compounds. For example, it was shown that insolubility in water is a common feature of thiol compounds and is not unique to BDET-M compounds. KEYWORDS: BDETH2, BDET-M, XAFS, AMD, XPS. Kamruz Md Zaman _______________________ July 31, 2008 _______________________ BENZENE-1,3-DIAMIDOETHANETHIOL (BDETH2) AND ITS METAL COMPOUNDS By Kamruz Md Zaman Dr. David A. Atwood ______________________________ Director of Dissertation Dr. Robert B. Grossman ______________________________ Director of Graduate Studies July 31, 2008 ______________________________ RULES FOR THE USE OF DISSERTATION Unpublished dissertations submitted for the Doctor’s degree and deposited in the University of Kentucky Library are as a rule open for inspection, but are to be used only with due regard to the rights of the authors. Biblio-graphical references may be noted, but quotations or summaries of parts may be published only with the permission of the author, and with the usual scholarly acknowledgements. Extensive copying or publication of the dissertation in whole or in part also requires the consent of the Dean of The Graduate School of the University of Kentucky. A library that borrows this dissertation for use by its patrons is expected to secure the signature of each user. Name Date ________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________ DISSERTATION Kamruz Md Zaman The Graduate School University of Kentucky 2008 BENZENE-1,3-DIAMIDOETHANETHIOL (BDETH2) AND ITS METAL COMPOUNDS ________________________ DISSERTATION ________________________ A dissertation submitted in partial fulfillment of the requirement for the degree of Doctor of Philosophy in the College of Arts and Science at the University of Kentucky By Kamruz Md Zaman Lexington, Kentucky Director: Dr. David A. Atwood, Professor of Chemistry Lexington, Kentucky 2008 Copyright © Kamruz Md Zaman 2008 DEDICATION This dissertation is dedicated to my late parents Mr. Abdul Wahed Sarker And Mrs. Ayesha Akhter Begum Who always inspired me to pursue higher education ACKNOWLEDGEMENTS I would like to thank my research supervisor, Dr. David A. Atwood, for his guidance and help in completing my doctoral program in chemistry at the University of Kentucky. I would also like to thank the other members of my graduate committee, Dr. J. Selegue, Dr. E. DeMoll and Dr. M. Mullen, for their suggestions and assistance. I would also like to thank my wife, Jewel, who always stood by me and extended her support to me in times of hardship. I would like to mention my daughter, Mahin, who always inspires me to do something special. Finally, I would like to thank my brothers and sisters for their encouragement and support. iii TABLE OF CONTENTS Acknowledgements…………………………………………………………………iii List of Tables……………………………………………………………………….vii List of Figures ……………………………………………………………………...viii List of Files…………………………………………………………………………x Chapter 1: Introduction 1.1 Statement of Purpose…………………………………………………....1 1.2 Metal and Metalloid Contaminants in the Environment………………..2 1.2.1 Iron……………………………………………………………3 1.2.2 Cobalt…………………………………………………………4 1.2.3 Nickel…………………………………………………………5 1.2.4 Copper………………………………………………………...6 1.2.5 Cadmium……………………………………………………...6 1.2.6 Mercury……………………………………………………….7 1.2.7 Lead…………………………………………………………...9 1.2.8 Arsenic………………………………………………………...9 1.3 Methods for Removing Heavy Metals………………………………….10 1.3.1 Phytoremediation……………………………………………..11 1.3.2 Constructed Wetlands………………………………………...13 1.3.3 Bioremediation………………………………………………..14 1.3.4 Activated Carbon Adsorption…………………………………17 1.3.5 Adsorbents from Agricultual and Forest Wastes……………...17 1.3.6 Ion-exchange Resins…………………………………………..18 1.3.7 Polythiol-functionalized Alumina Membranes………………..19 1.3.8 Nanoporous Adsorbent Materials……………………………..19 1.3.9 Crown Thioethers……………………………………………...21 1.3.10 Polymeric Chelating Fibers…………………………………..22 1.3.11 Tunable Biopolymers………………………………………...22 1.3.12 Extraction from Aqueous Solutions………………………….24 1.3.12.2 Surfactants………………………………………………….24 1.3.13 Chemical Precipitation……………………………………….25 1.4 Conclusions……………………………………………………………..44 Chapter 2: Metal Compounds of BDETH2 2.1 Overview………………………………………………………………..46 2.2 Alkali and Alkaline Earth Metal Thiolates……………………………..47 2.2.1 Alkali Metal Thiolates………………………………………..48 2.2.2 Alkali Metal Compounds of BDETH2………………………..49 2.2.3 Alkaline Earth Metal Thiolates……………………………….53 2.2.4 Alkaline Earth Metal Compounds of BDETH2……………....54 iv 2.2.5 Conclusions…………………………………………………..55 2.3 Transition Metal Thiolates……………………………………………..56 2.3.1 Transition Metal Complexes of BDETH2................................57 2.3.2 Conclusions…………………………………………………..60 2.4 Main Group Metal Thiolates…………………………………………...61 2.4.1 Cadmium Complexes………………………………………...62 2.4.2 Mercury Complexes………………………………………….63 2.4.3 Tin Complexes……………………………………………….64 2.4.4 Lead Complexes……………………………………………..66 2.4.5 Arsenic Compounds…………………………………………68 2.4.6 Main Group Compounds of BDETH2……………………….71 2.5 Attempted Metallation of BDET-Metal Compounds………………….85 2.6 Experimental…………………………………………………………...87 2.6.1 General Considerations………………………………………87 2.6.2 Syntheses…………………………………………………….88 2.6.3 Leaching Studies…………………………………………….97 Chapter 3: Attempted Alkylalumination 3.1 Overview………………………………………………………………99 3.2 Synthesis and Characterization……………………………………......101 3.3 Experimental………………………………………………………......106 3.4 Conclusions……………………………………………………………107 Chapter 4: N,N'-Bis(2-mercaptoethyl) oxalamide (MOA) 4.1 Overview………………………………………………………………109 4.2 Synthesis and Characterization………………………………………..109 4.3 Experimental…………………………………………………………..114 4.4 Conclusions……………………………………………………………117 Chapter 5: Metal Compounds of Dithiothreitol (DTT) 5.1 Overview……………………………………………………………...119 5.2 Synthesis and Characterization…………………………………….....120 5.3 Experimental………………………………………………………….124
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