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Synthesis, Structure Features and Application of Pro-Azaphsphatranes As Catalysts and Strong Non-Ionic Bases in Organic Synthesis " (1994)

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Synthesis, Structure Features and Application of Pro-Azaphsphatranes As Catalysts and Strong Non-Ionic Bases in Organic Synthesis Iowa State University Capstones, Theses and Retrospective Theses and Dissertations Dissertations 1994 Synthesis, structure features and application of pro- azaphsphatranes as catalysts and strong non-ionic bases in organic synthesis Jiansheng Tang Iowa State University Follow this and additional works at: https://lib.dr.iastate.edu/rtd Part of the Medicinal and Pharmaceutical Chemistry Commons, Medicinal Chemistry and Pharmaceutics Commons, Medicinal-Pharmaceutical Chemistry Commons, Organic Chemistry Commons, and the Polymer Chemistry Commons Recommended Citation Tang, Jiansheng, "Synthesis, structure features and application of pro-azaphsphatranes as catalysts and strong non-ionic bases in organic synthesis " (1994). Retrospective Theses and Dissertations. 10651. https://lib.dr.iastate.edu/rtd/10651 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 Retrospective Theses and Dissertations by an authorized administrator of Iowa State University Digital Repository. For more information, please contact [email protected]. INFORMATION TO USERS This manuscript has been reproduced from the microfilm master. UMI films the text directly from the original or copy submitted. Thus, some thesis and dissertation copies are in typewriter face, while others may be from any type of computer printer. 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 bleedthrough, substandard margins, and improper alignment can adversely affect reproduction. In the unlikely event that the author did not send UMI 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. Oversize materials (e.g., maps, drawings, charts) are reproduced by sectioning the original, beginning at the upper left-hand corner and continuing from lefr to right in equal sections with small overlaps. Each original is also photographed in one exposure and is included in reduced form at the back of the book. Photographs included in the original manuscript have been reproduced xerographically in this copy. Higher quality 6" x 9" black and white photographic prints are available for any photographs or illustrations appearing in this copy for an additional charge. Contact UMI directly to order. University Microfilms International A Bell & Howell Information Company 300 North Zeeb Road, Ann Arbor. Ml 48106-1346 USA 313/761-4700 800/521-0600 Order Number 9424265 Synthesis, structure features and application of pro-azaphosphatranes as catalysts and strong non-ionic bases in organic synthesis Tang, Jiansheng, Ph.D. Iowa State University, 1994 UMI 300 N. Zeeb Rd. Ann Arbor, Ml 48106 Synthesis, structure features and application of pro-azaphsphatranes as catalysts and strong non-ionic bases in organic synthesis by Jiansheng Tang A Dissertation Submitted to the Graduate Faculty in Partial Fulfillment of the Requirements for the Degree of DOCTOR OF PHILOSOPHY Department: Chemistry Major; Organic Chemistry Approved: Signature was redacted for privacy. In Charge of Major Work Signature was redacted for privacy. For the Major Department Signature was redacted for privacy. For the Graduate College Iowa State University Ames, Iowa 1994 11 DEDICATION To my wife, son, parents, brother and sisters for their love and to the memory of my father ni TABLE OF CONTENTS Page GENERAL INTRODUCTION 1 PAPER 1. AN IMPROVED SYNTHESIS OF THE STRONG BASE P(MeNCH2CH2)3N 6 ABSTRACT 7 COMMUNICATION 8 ACKNOWLEDGMENTS 10 REFERENCES AND NOTES 11 SUPPLEMENTARY MATERIALS 12 PAPER 2. STEPWISE TRANSANNULAR BOND FORMATION BETWEEN THE BRIDGEHEAD ATOMS IN ZP(MeNCH2CH2)3N SYSTEMS 14 ABSTRACT 15 COMMUNICATION 16 ACKNOWLEDGMENTS 21 REFERENCES 22 SUPPLEMENTARY MATERIALS 25 PAPER 3. SYNTHESIS OF EXCEEDINGLY STRONG NON-IONIC BASES: RN=P(MeNCH2CH2)3N 71 ABSTRACT 72 INTRODUCTION 73 EXPERIMENTAL SECTION 75 DISCUSSION 84 CONCLUDING REMARKS 93 ACKNOWLEDGMENTS 94 iv REFERENCES 95 SUPPLEMENTARY MATERIALS 97 PAPER 4. SYNTHESIS AND REACTIVITY PATTERNS OF NEW PRO-AND QUASI-AZAPHOSPHATRANES ZP(MeNCH2CH2)3N 104 ABSTRACT 105 INTRODUCTION 106 DISCUSSION 108 EXPERIMENTAL SECTION 115 ACKNOWLEDGMENTS 123 REFERENCES 124 PAPER 5. P(MeNCH2CH2)3N AS A SUPERIOR CATALYST IN THE CONVERSION OF ISOCYANATES TO ISOCYANURATES 126 SUMMARY/JUSTIFICATION 127 COMMUNICATION 128 ACKNOWLEDGMENTS 134 REFERENCES 135 PAPER 6. SELECTIVE AND EFFICIENT SYNTHESIS OF PERHYDR0-1,3,5-TRIAZINE.2,4,6-TRI0NES AND CARBODIIMIDES FROM ISOCYANATES USING ZP(MeNCH2CH2)3N CATALYSTS 137 ABSTRACT 138 INTRODUCTION 139 RESULTS AND DISCUSSION 141 EXPERIMENTAL SECTION 156 ACKNOWLEDGMENTS 167 REFERENCES 168 V SUPPLEMENTARY MATERIALS 171 PAPER 7. NON-IONIC SUPERBASE-PROMOTED SYNTHESIS OF PYRROLS AND OXAZOLES: FACILE SYNTHESIS OF PORPHYRINS AND a-C-ACYLAMINO ACID ESTERS 178 ABSTRACT 179 INTRODUCTION 180 RESULTS AND DISCUSSION 182 CONCLUSIONS 198 EXPERIMENTAL SECTION 199 ACKNOWLEDGMENTS 215 REFERENCES 216 GENERAL CONCLUSIONS 218 ACKNOWLEDGMENTS 225 1 GENERAL INTRODUCTION An Explanation of the Dissertation Organization. This dissertation contains nine sections. The first section is a general introduction containing a statement of the project and an outline of the goals of the research described herein. Each of the subsequent seven sections (paper 1 to paper 7) represents research results as they have been published or submitted for journal publication. The numbering of compounds, figures, schemes, tables and references are independent in each paper. The final section is a summary of the results achieved, some suggestions for additional research and references. All contributors to the work presented herein are acknowledged in each chapter and a general acknowledgment is presented in the end of the dissertation. A Statement of the Research Project. Phosphorus is ubiquitous in our world. It is the key element in the genetic tape that guides the reproduction of all species. It is essential to all forms of life. It is one of the major elements found in many solid-state metal materials such as GaP and InP. Its salts leaven our food , and clean our teeth and water. Its organic derivatives reduce the flammability of materials around us, kill insects and bacteria as highly effective but low toxicity pesticides, and kill cancers as chemo-therapeutics. In other words, the application of phosphorus compounds impacts virtually every area of "everyday living".l In a more basic sense, its chemistry, which is so important in life, provides many conceptual challenges in topics from unusual bonding patterns and stereochemistry to reaction kinetics that control important chemical processes. Since the end of the 19th century, the study of organic phosphorus compounds has developed at an ever increasing rate. One can identify, however, several periods in subsequent years where important discoveries have led to rapid increases in interest in phosphorus compounds. The discovery of the toxic and insecticidal properties of such compounds by 2 Schrader and others^ in 1930s has created a whole new industry. Reports^ in the 1950s of the conversion of carbonyl compounds to aUcenes by Wittig opened a completely new area in the use of organic phosphorus compounds in organic synthesis. The Wittig reaction in which triphenyl phosphine is involved was recognized with a Nobel Prize. This reaction along with the Horner-Emmons modification^ continues to be an important tool for the carbon-carbon bond construction in modern synthedc organic chemistiy. Other synthetically useful reactions coupled with phosphorus(III) compounds into phosphorus(V) compounds includes the Michaelis-Abuzov reaction^, the reactions using reagents formed by the combination of tertiary phosphines or triaryl phosphite with carbon tetrahalides or with halogens,^ the Mukaiyama redox condensation^ and the Mitsunobu esterification reaction.* The use of effective phosphorus ligands in homogeneous catalysis opened up another new area in the use of phosphorus compounds in synthetic organic chemistryIn fact, use of a chiral phosphorus- Rh(I) complex introduced in Monsanto's L-Dopa synthesis in 1970's is the first commercialized catalytic asymmetric process. In the late 1980's, Schwesinger reported the tetraphosphazene P4-r-Bu (i.e. f-BuN=P[N=P(NMe2)3]3) to be the strongest non-ionic base. This discovery opened up a third area of the use of organophosphorus compounds in synthetic organic chemistry!^ which was recognized with the 1992 Fluka new reagent prize. However, P4-f-Bu is very difficult to synthesize and, though commercially available, it is very expensive. Since the late 1970s, the chemistry of atranes of groups 13 to 15 and also many metallic examples has been extensively explored by the Verkade group and others^^ because of its intrinsic interest and the possibility that volatile examples may serve as precursors for metal and non-metal nitrides for a variety of electronic applications and as hard-surface coatings for protection against corrosion and wear. In addition, pro-phosphatranes^^^ and pro- azaphosphatranes^S have also been synthesized and found to be bases stronger than the medium strong non-ionic base Proton Sponge. However, their actual basicities were not 3 measured and their applications as non-ionic superbases and catalysts in synthetic organic chemistry were not yet
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