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Sterically Bulky Nitrogen Based Ligands: New Chelate Complexes and Applications in Dehydrocoupling Catalysis

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Sterically Bulky Nitrogen Based Ligands: New Chelate Complexes and Applications in Dehydrocoupling Catalysis University of Windsor Scholarship at UWindsor Electronic Theses and Dissertations Theses, Dissertations, and Major Papers 2005 Sterically bulky nitrogen based ligands: New chelate complexes and applications in dehydrocoupling catalysis. Jason Douglas Masuda University of Windsor Follow this and additional works at: https://scholar.uwindsor.ca/etd Recommended Citation Masuda, Jason Douglas, "Sterically bulky nitrogen based ligands: New chelate complexes and applications in dehydrocoupling catalysis." (2005). Electronic Theses and Dissertations. 3593. https://scholar.uwindsor.ca/etd/3593 This online database contains the full-text of PhD dissertations and Masters’ theses of University of Windsor students from 1954 forward. These documents are made available for personal study and research purposes only, in accordance with the Canadian Copyright Act and the Creative Commons license—CC BY-NC-ND (Attribution, Non-Commercial, No Derivative Works). Under this license, works must always be attributed to the copyright holder (original author), cannot be used for any commercial purposes, and may not be altered. Any other use would require the permission of the copyright holder. Students may inquire about withdrawing their dissertation and/or thesis from this database. For additional inquiries, please contact the repository administrator via email ([email protected]) or by telephone at 519-253-3000ext. 3208. 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 comer and continuing from left to right in equal sections with small overlaps. ProQuest Information and Learning 300 North Zeeb Road, Ann Arbor, Ml 48106-1346 USA 800-521-0600 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Sterically Bulky Nitrogen Based Ligands: New Chelate Complexes and Applications in Dehydrocoupling Catalysis By Jason Douglas Masuda A Dissertation Submitted to the Faculty of Graduate Studies and Research Through the Department of Chemistry and Biochemistry In Partial Fulfillment of the Requirements for The Degree of Doctor of Philosophy At the University of Windsor Windsor, Ontario, Canada 2005 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Library and Bibliotheque et 1*1 Archives Canada Archives Canada 0-494-09721-3 Published Heritage Direction du Branch Patrimoine de I'edition 395 Wellington Street 395, rue Wellington Ottawa ON K1A 0N4 Ottawa ON K1A0N4 Canada Canada Your file Votre reference ISBN: Our file Notre reterence ISBN: NOTICE: AVIS: The author has granted a non­ L'auteur a accorde une licence non. exclusive exclusive license allowing Library permettant a la Bibliotheque et Archives and Archives Canada to reproduce, Canada de reproduire, publier, archiver, publish, archive, preserve, conserve, sauvegarder, conserver, transmettre au public communicate to the public by par telecommunication ou par I'lnternet, preter, telecommunication or on the Internet, distribuer et vendre des theses partout dans loan, distribute and sell theses le monde, a des fins commerciales ou autres, worldwide, for commercial or non­ sur support microforme, papier, electronique commercial purposes, in microform, et/ou autres formats. paper, electronic and/or any other formats. The author retains copyright L'auteur conserve la propriete du droit d'auteur ownership and moral rights in et des droits moraux qui protege cette these. this thesis. Neither the thesis Ni la these ni des extraits substantiels de nor substantial extracts from it celle-ci ne doivent etre imprimes ou autrement may be printed or otherwise reproduits sans son autorisation. reproduced without the author's permission. In compliance with the Canadian Conformement a la loi canadienne Privacy Act some supporting sur la protection de la vie privee, forms may have been removed quelques formulaires secondaires from this thesis. ont ete enleves de cette these. While these forms may be included Bien que ces formulaires in the document page count, aient inclus dans la pagination, their removal does not represent il n'y aura aucun contenu manquant. any loss of content from the thesis. 8 * 1 Canada Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. © 2005 Jason Douglas Masuda Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Abstract Routes to the sterically bulky chelating N,N’-based ligand systems (C 6H31- Pr2)NC(Me)CH2PPh2(NC6H3z-Pr2) and /-Pr2C 6H3N(C(Me)NC6H3/-Pr2)2 have been developed and their chemistries with Group 13 metals, specifically aluminum and gallium have been investigated. Highlights from this work include the isolation of neutral Iigand-A1R2 species (R = Me, H) which in turn form cationic species when reacted with B(C 6F5)3 or [Ph 3C][B(C6F5)4]. In addition, the N-imidoyl amidine ligand i- Pr2C6H3N(C(Me)NC6H3/-Pr2)2 reacts with three equivalents of AlMe 3 to give the species [(z-Pr2C6H3N(C(Me)NC6H3/-Pr2)2)AlMe2][Al2Me7], which upon heating loses CH4 to give the neutral species (z'-Pr2C 6H3N(C(=:CH2)NC6H3Z-Pr2)(C(Me)NC6H32-Pr2)AlMe2. Kinetic studies have provided insights to the mechanism of this reaction. A number of late transition metal halide complexes of the above mentioned ligand systems have been formed and derivatization reactions have been performed resulting, in some cases, isolation of systems not common in the literature such as the borane stabilized nickel (I) hydride species (z-Pr2C 6H3N)C(Me)(NC6H32-Pr2)C(Me)(NC6H3Z- Pr2)Ni(p-H)2BEt2. In addition, the sterically bulky P-diimine based terminally bound rhodium dinitrogen complex, NacNacRh(N2)(COE) is isolated and is the first example of a rhodium dinitrogen compound supported by a nitrogen-based ligand system. Finally, a new titanium-based phosphine dehydrocoupling catalyst, CpTi(NPt- Bu3)(CFI2)4, has been discovered and applications to the dehydrocoupling of primary and secondary phosphines has been investigated. Dehydrocoupling of PhPH2 results in a number of intermediates: PhP(H)(PhP)x(H)PPh (X = 0, 1), (PhP)x (X = 4, 6) and ultimately (PhP)s as the thermodynamically favored product. Reaction of 1,2- bisphosphinobenzene with catalytic amounts of CpTi(NP/-Bu3)(CH 2)4 initially gives the dehydrocoupled dimer as an intermediate to the the previously reported Pi6 macrocycle. Dehydrocoupling of 4,5-dimethyl-1,2-bisphosphinobenzene also gives the dimer as an intermediate, however, upon further reaction the unique P 10 containing molecule is isolated. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. V For Rebecca Ann Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. vi Acknowledgements Most importantly, I would like to thank my wife Raechelle for putting up with a husband in graduate school, not only for a Master’s degree but then a Ph.D. on top of that. Rather than repeating all of the sappy romantic stuff I wrote in my M.Sc. thesis, I have elected to keep this short and sweet: Yes Honey, we will buy a house once I get a ‘real’ job. Thank you for supporting me through these last 5 years of graduate school. The following people are also thanked: My Tittle sister’ Jenny McCahill for understanding (or putting up with) my weird ways and being the best fumehood/glovebox partner anyone could ever wish for. Sharonna Greenberg for the chemistry chats, family meals and going through my thesis word by word. Greg Welch for being my last drinking bud and understanding chemistry the way that I do. A nod is deserved for all of the other previous and current Stephan Group members that were present during my stay especially to Denise Walsh, Sarah Hawkeswood, Chris Fraser and Andrew ‘3 L chaps’ Fenwick. Mike Fuerth is thanked for the jokes and showing me the ins and outs of working on the NMR spectrometers. Drs. Chuck Macdonald, Rob Schurko, Sam Johnson and Jim Green are thanked for answering all of my questions, giving me odd chemicals and providing advice. Dr. Pingrong Wei is thanked for collecting data for some of the crystal structures in this work. Xudong Shen is acknowledged for initiating the work on the dehydrocoupling of Mes*PH 2. Finally I would like to thank Dr. Doug Stephan for being an excellent supervisor, providing me nearly complete freedom in the lab, which has been immensely helpful at expanding my creativity, while always subtly pushing me in the right direction to achieve my goals. I could not have asked for a better supervisor! Reproduced with permission of the copyright owner. Further reproduction
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