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A Modified Synthesis, C-Functionalization, Resolution And University of New Hampshire University of New Hampshire Scholars' Repository Doctoral Dissertations Student Scholarship Spring 2009 A modified synthesis, C-functionalization, esolutionr and racemization kinetics of cross -bridged tetraazamacrocycles Antoinette Yolanda Odendaal University of New Hampshire, Durham Follow this and additional works at: https://scholars.unh.edu/dissertation Recommended Citation Odendaal, Antoinette Yolanda, "A modified synthesis, C-functionalization, esolutionr and racemization kinetics of cross -bridged tetraazamacrocycles" (2009). Doctoral Dissertations. 481. https://scholars.unh.edu/dissertation/481 This Dissertation is brought to you for free and open access by the Student Scholarship at University of New Hampshire Scholars' Repository. It has been accepted for inclusion in Doctoral Dissertations by an authorized administrator of University of New Hampshire Scholars' Repository. For more information, please contact [email protected]. A MODIFIED SYNTHESIS, C-FUNCTIONALIZATION, RESOLUTION AND RACEMIZATION KINETICS OF CROSS-BRIDGED TETRAAZAMACROCYCLES By Antoinette Yolanda Odendaal B.A., University of Southern Maine, 2003 DISSERTATION Submitted to the University of New Hampshire in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy in Chemistry May 2009 UMI Number: 3363725 INFORMATION TO USERS The quality of this reproduction is dependent upon the quality of the copy submitted. Broken or indistinct print, colored or poor quality illustrations and photographs, print bleed-through, substandard margins, and improper alignment can adversely affect reproduction. In the unlikely event that the author did not send a complete manuscript and there are missing pages, these will be noted. Also, if unauthorized copyright material had to be removed, a note will indicate the deletion. UMI® UMI Microform 3363725 Copyright 2009 by ProQuest LLC All rights reserved. This microform edition is protected against unauthorized copying under Title 17, United States Code. ProQuest LLC 789 East Eisenhower Parkway P.O. Box 1346 Ann Arbor, Ml 48106-1346 This dissertation has been examined and approved. ttionlDirector Weisman Professor of Chemistry S^Z>(AJ~*W^&)' Edward H. Wong Professor of Chemistry Charles K. Zercher Professor of Chemistry Arthur Greenberg Professor of Chemistry Donald C. Sundberg Emeritus Professor of Material Science te R\o daft Date DEDICATION In memory of my grandfather Jacob Smit September 2, 1920-May 4, 1989 in ACKNOWLEDGMENTS Funding Sources: Chemistry Department Teaching Assistantship (September 2003-Decmeber 2005). NSF GK-12 PROBE Fellowship (May 2006-May 2007). NIH Research Assistantship (January 2006-May 2006, May 2007-January 2009). People: I thank my advisor Gary Weisman and my co-advisor Ed Wong for their mentorship, guidance and support over the years. I would like to acknowledge my committee members and thank them for all their suggestions. This research was aided directly and indirectly by contributions from the Weisman/Wong group members past and present. I would also like to thank the Chemistry Department at UNH and Professors Charles Zercher, Arthur Greenberg, Denny Chasteen, Howard Mayne, Roy Planalp, Glen Miller, Richard Johnson, Sterling Tomellini, Chris Bauer, Pat Wilkinson, Meg Greenslade, Rudy Seitz. I greatly appreciate all the help and support from Cindi Rohwer and Peggy Torch. Special thanks: Abe, Nicolette, Orjana and my family. iv TABLE OF CONTENTS DEDICATION iii ACKNOWLEDGMENTS iv TABLE OF CONTENTS v LIST OF FIGURES xi LIST OF SCHEMES xiv LIST OF TABLES xviii LIST OF GRAPHS xix ABSTRACT xx CHAPTER 1: A TRICYCLIC BISAMINAL ROUTE TO CROSS-BRIDGED CYCLAM AND HOMOCYCLEN, AND THE MICROWAVE- ASSISTED DOUBLE REDUCTIVE RING OPENING OF DIBENZYL BISAMINAL SALTS I. Introduction 1 II. Background 10 III. Results and Discussion 23 1. Synthesis of A^,Ar'-bis(2-aminoethyl)-l,3-propanediamine (23). 23 2. Synthesis of cw-octahydro-lH,4H,7H-l,3a,6a,9- 24 tetraazaphenalene (49). 3. Synthesis of cz's-decahydro-lH^H-Sa^a^a, 10a- 24 tetraazapyrene (13). 4. Synthesis of c«-decahydro-5H-2a,4a,7a,9a- 26 tetraazacyclopentaphenalene (12). 5. Microwave-assisted reductive ring opening of 14,15 and 16. 27 6. Alkylation of c/s/fr<ms-decahydro-lH,6H-3a,5a,8a,10a- 29 tetraazapyrene (13) followed by microwave-assisted reductive ring-opening. 7. Synthesis of 2a,7a-(prop-2-en-l-yl)decahydro-5H-4a,9a- 32 diaza-2a,7a-diazoniacyclopenta[cd]phenalene dibromide (54). 8. Synthesis of 4,1 l-di(prop-2-en-l-yl)-l,4,8,11- 34 tetraazabicyclo[6.5.2]pentadecane (55). 9. Synthesis, characterization, and properties of copper(II) 1,4,8,11- 35 tetraazabicyclo[6.5.2]pentadecane (9) complex. 10. Synthesis and copper (II) complexation of 4,11-bis- 39 (carboxymethyl)-1,4,8,1 l-tertaazabicyclo[6.5.2]pentadecane (58). IV Conclusions 45 CHAPTER 2: PROGRESS TOWARDS A C-FUNCTIONALIZED CROSS- BRIDGED CYCLAM I. Introduction 46 II. Background 49 III. Results and Discussion 54 VI 1. Attempted synthesis of a carbonyl-functionalized cyclam 54 bisaminal 85. 2. The synthesis of c/s-2-methylidenedecahydro-lH,6H- 56 3a,5a,8a,l Oa-tetraazapyrene (92). 3. Attempted ozonolysis of 92. 59 4. Attempted alkylation of 92. 60 5. The synthesis of c/s-3a,8a-bis(phenylmethyl)-2- 60 methylidenedecahydro-lH,6H-5a,10a-diaza-3a,8a- diazoniapyrene dibromide (98). 6. The synthesis of 4,11 -bis(phenylmethyl)-6- 61 methylidene, 1,4,8,1 l-tetraazabicyclo[6.6.2]hexadecane (99). 7. The synthesis of c«-2-methylidine-3a-8a-bis(naphthalene-2- 63 ylmethyl)decahydro-l H,6H-5a,l 0a-diaza-3a-8a-diazoniapyrene (100). 8. The synthesis of 6-methylidene-4,11 -bis(napththalene-2- 64 methyl)-1,4,8,1 l-tetraazabicyclo[6.6.2]hexadecane (101). 9. The attempted deprotection of 99 and 101. 64 10. The synthesis of cw-decahydro-lH,6H-3a,3a,10a-tetraazapyren- 66 2-yl methanol (104). 11. The synthesis of 3a,8a-di(phenylmethyl)-2- 71 (hydroxymethyl)decahydro-1 H,6H,a, 10a-diaza-3a,8a- diazoniapyrene (107). 12. The synthesis of 4,11-di(phenylmethyl)-1,4,8,11- 71 vii tetraazabicyclo[6.6.2]hexadec-6-yl) methanol dihydrobromide monohydrate (108«2HBr»H2O). IV. Conclusions 73 CHAPTER 3: RESOLUTION OF RACEMIC CROSS-BRIDGED CYCLAM BY DIASTEREOMERIC SALT FORMATION AND THE RACEMIZATION KINETICS OF ENANTIOPURE CROSS- BRIDGED CYCLAM I. Introduction 74 II. Background 76 III. Results and Discussion 83 1. Resolution of bicyclo[6.6.2]tetraamines by selective 83 crystallization of their diastereomeric salt mixtures. 1.1. Preparation of 4,1 l-bis(phenylmethyl)-l,4,8,ll- 84 tetraazabicyclo[6.6.2]hexadecane (5',5)-(+)-dibenzoyl- D-tartrate (1:1 diastereomeric mixture) (119). 1.2. Preparation of 4,1 l-bis(phenylmethyl)-l,4,8,11- 85 tetraazabicyclo[6.6.2]hexadecane L-(+)-tartrate (1:1 diastereomeric mixture) (120). 1.3. Preparation of 1,4,8,11 -tetraazabicyclo[6.6.2]hexadecane 86 di-(15)-(+)-camphorsulfonate (1:1 diastereomeric mixture) (121). viii 1.4. Preparation of 1,4,8,11 -tetraazabicyclo[6.6.2]hexadecane 86 (5',5)-(+)-dibenzoyl-D-tartrate (1:1 diastereomeric mixture) (122). 1.5. Preparation of 1,4,8,11 -tetraazabicyclo[6.6.2]hexadecane 87 L-(+)-tartrate (1:1 diastereomeric mixture) (123). 1.6. Preparation of 1,4,8,11 -tetraazabicyclo[6.6.2]hexadecane 93 D-(-)-tartrate (1:1 diastereomeric mixture) (125). 2. Racemization kinetics of enantiopure (S^-IO. 96 IV. Conclusions 102 CHAPTER 4: COMPUTATIONAL INVESTIGATION OF NITROGEN LONE PAIR ORIENTATION EFFECTS ON THE METHINE NMR PARAMETERS OF TRICYCLIC ORTHOAMIDES I. Introduction 103 II. Background 105 III. Results and Discussion 106 1. Computational methodology 106 2. Computational results 107 IV. Conclusions 111 CHAPTER 5: EXPERIMENTAL DETAILS I. General methods 112 II. Solvents 113 ix III. Reagents 115 IV. Column Chromatography 116 V. Experimental Procedures 116 VI. Fractional Crystallization of 123 (1:1 diastereomeric salt mixture). 144 VII. Recovery of enantiopure free base (S,S)-10 and the preparation of 147 (S,S)-4,\ 1-bis-(carbo-tert-butoxymethyl)-1,4,8,11- tetraazabicyclo[6.6.2]hexadecane (133). VIII. Optical rotation of (S.S^cross-bridged cyclam (10). 150 IX. Kinetics of racemization of cross-bridged cyclam (10). 152 APPENDIX A: SPECTRAL INDEX 156 APPENDIX B: COMPOUND INDEX 210 REFERENCES 216 x LIST OF FIGURES Figure Page 1 Cis and trans configurational geometries. 3 2 Cross-bridged cyclam (10). 3 3 Copper(II) complexes of 3 and 10 with the hydrogens omitted. 7 4 Ligands CB-TE2A (20), TE2A (21) and bioconjugate 22. 8 13 ! 5 C{ H} and 'HNMR spectra (C6D6) of 13 containing a minor 30 amount of 40. U : 6 C{ H} and 'HNMR spectra of 16 in D20 (ref. MeCN). 31 7 "C^H} and 'H NMR spectra of dibenzyl cross-bridged cyclam 19 in 32 C6D6. 8 [CuC104'9](C104) Dimer (extra C104 omitted for clarity). 37 9 The copper(II) complexes of 8 and 10. 38 = 10 Visible spectra (A,max 575 nm) and pseudo-first order kinetics plot of 39 the acid-decomplexation of [CuC104«9](C104) in 5M HC1 at 50 °C. 11 X-ray crystal structure of Cu«58 with the hydrogens omitted. 41 12 Visible spectra (Xmax = 607 nm) and pseudo-first order kinetics plot of 43 the acid-decomplexation of Cu«58 in 5M HC1 at 50 °C. 13 Comparative kinetic inertness of Cu»60, Cu»58 and Cu»20. 43 14 Comparative X-ray structures of Cu»60, Cu»58 and Cu»20. 44 15 The *H NMR spectra of 92 and 93 in CDC13. 58 16 Ortep diagram of 98 (hydrogens omitted). 61 xi 17 Ortep diagram of the 99«HPF6 salt (ligand hydrogens omitted). 63 18 Possible hydroboration-oxidation reaction outcomes. 67 19 Approximate coupling constants expected for H2eq of 104 and 105. 68 20 Crystal structure of 104»2HBr (ligand hydrogens omitted). 69 21 The intermolecular hydrogen bonds between two 104 molecules 70 (ligand hydrogens omitted).
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