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Transition Metal Catalyzed Hydroarylation of Multiple Bonds: Exploration of Second Generation Ruthenium Catalysts and Extension to Copper Systems

Description: Catalysts provide foundational technology for the development of new materials and can enhance the efficiency of routes to known materials. New catalyst technologies offer the possibility of reducing energy and raw material consumption as well as enabling chemical processes with a lower environmental impact. The rising demand and expense of fossil resources has strained national and global economies and has increased the importance of accessing more efficient catalytic processes for the conversion of hydrocarbons to useful products. The goals of the research are to develop and understand single-site homogeneous catalysts for the conversion of readily available hydrocarbons into useful materials. A detailed understanding of these catalytic reactions could lead to the development of catalysts with improved activity, longevity and selectivity. Such transformations could reduce the environmental impact of hydrocarbon functionalization, conserve energy and valuable fossil resources and provide new technologies for the production of liquid fuels. This project is a collaborative effort that incorporates both experimental and computational studies to understand the details of transition metal catalyzed C-H activation and C-C bond forming reactions with olefins. Accomplishments of the current funding period include: (1) We have completed and published studies of C-H activation and catalytic olefin hydroarylation by TpRu{l_brace}P(pyr){sub 3}{r_brace}(NCMe)R (pyr = N-pyrrolyl) complexes. While these systems efficiently initiate stoichiometric benzene C-H activation, catalytic olefin hydroarylation is hindered by inhibition of olefin coordination, which is a result of the steric bulk of the P(pyr){sub 3} ligand. (2) We have extended our studies of catalytic olefin hydroarylation by TpRu(L)(NCMe)Ph systems to L = P(OCH{sub 2}){sub 3}CEt. Thus, we have now completed detailed mechanistic studies of four systems with L = CO, PMe{sub 3}, P(pyr){sub 3} and P(OCH{sub 2}){sub 3}CEt, which has provided a comprehensive understanding of the impact of steric and electronic parameters of 'L' on the catalytic hydroarylation of olefins. ...
Date: February 17, 2011
Creator: Gunnoe, T. Brent
Partner: UNT Libraries Government Documents Department

Activation of Carbon-Hydrogen Bonds via 1,2-Addition across M-X (X = OH or NH2) Bonds of d6 Transition Metals as a Potential Key Step in Hydrocarbon Functionalization: A Computational Study

Description: Article discussing a computational study on the activation of carbon-hydrogen bonds via 1,2-addition across M-X (X = OH or NH2) bonds of d6 transition metals as a potential key step in hydrocarbon functionalization.
Date: October 6, 2007
Creator: Cundari, Thomas R., 1964-; Grimes, Thomas V. & Gunnoe, T. Brent
Partner: UNT College of Arts and Sciences

Octahedral [TpRu(PMe3)2OR]n+ Complexes (Tp = hydridotris(pyrazolyl)borate; R = H or Ph; n = 0 or 1): Reactions at Ru(II) and Ru(III) Oxidation States with Substrates that Possess Carbon-Hydrogen Bonds

Description: This article discusses octahedral [TpRu(PMe3)2OR]n+ Complexes (Tp = hydridotris(pyrazolyl)borate.
Date: September 15, 2006
Creator: Feng, Yuee; Gunnoe, T. Brent; Grimes, Thomas V. & Cundari, Thomas R., 1964-
Partner: UNT College of Arts and Sciences

Synthesis and Reactivity of a Coordinatively Unsaturated Ruthenium(II) Parent Amido Complex: Studies of X-H Activation (X = H or C)

Description: Article discussing the synthesis and reactivity of a coordinatively unsaturated Ruthenium(II) parent amido complex and studies of X-H activation (X = H or C).
Date: April 27, 2004
Creator: Conner, David; Jayaprakash, K. N.; Cundari, Thomas R., 1964- & Gunnoe, T. Brent
Partner: UNT College of Arts and Sciences

Combined Experimental and Computational Studies on the Nature of Aromatic C-H Activation by Octahedral Ruthenium(II) Complexes: Evidence for σ-Bond Metathesis from Hammett Studies

Description: Article discussing combined experimental and computational studies on the nature of aromatic C-H activation by octahedral ruthenium(II) complexes of the type TpRu(L)(NCMe)R [Tp = hydridotris(pyrazolyl)borate; R = alkyl or aryl; L = CO or PMe3].
Date: November 27, 2007
Creator: DeYonker, Nathan J.; Foley, Nicholas A.; Cundari, Thomas R., 1964-; Gunnoe, T. Brent & Petersen, Jeffrey L.
Partner: UNT College of Arts and Sciences

Reactions of TpRu(CO) (NCMe) (Me) (Tp = Hydridotris(pyrazolyl)borate) with Heteroaromatic Substrates: Stoichiometric and Catalytic C-H Activation

Description: Article discussing reactions of TpRu(CO)(NCMe)(Me) (Tp = Hydridotris(pyrazolyl)borate) with heteroaromatic substrates and stoichiometric and catalytic C-H activation.
Date: October 15, 2004
Creator: Pittard, Karl A.; Lee, John P.; Cundari, Thomas R., 1964-; Gunnoe, T. Brent & Petersen, Jeffrey L.
Partner: UNT College of Arts and Sciences

Carbon-Oxygen Bond Formation via Organometallic Baeyer-Villiger Transformations: A Computational Study on the Impact of Metal Identity

Description: Article discussing a computational study on the impact of metal identity and carbon-oxygen bond formation via organometallic Baeyer-Villiger transformations.
Date: December 20, 2011
Creator: Figg, Travis M.; Webb, Joanna R.; Cundari, Thomas R., 1964- & Gunnoe, T. Brent
Partner: UNT College of Arts and Sciences

Facile and Regioselective C H Bond Activation of Aromatic Substrates by an Fe (II) Complex Involving a Spin-Forbidden Pathway

Description: Article discussing facile and regioselective C H bond activation of aromatic substrates by an Fe(II) complex involving a spin-forbidden pathway.
Date: February 27, 2013
Creator: Kalman, Steven E.; Petit, Alban; Gunnoe, T. Brent; Ess, Daniel H.; Cundari, Thomas R., 1964- & Sabat, Michal
Partner: UNT College of Arts and Sciences

Comparative Reactivity of TpRu(L)(NCMe)Ph (L = CO or PMe3): Impact of Ancillary Ligand L on Activation of Carbon-Hydrogen Bonds Including Catalytic Hydroarylation and Hydrovinylation/Oligomerization of Ethylene

Description: Article discussing research on the comparative reactivity of TpRu(L)(NCMe)Ph (L = CO or PMe3) and the impact of ancillary ligand L on activation of carbon-hydrogen bonds including catalytic hydroarylation and hyrdovinylation/oligomerization of ethylene.
Date: May 9, 2007
Creator: Foley, Nicholas A.; Lail, Marty; Lee, John P.; Gunnoe, T. Brent; Cundari, Thomas R., 1964- & Petersen, Jeffrey L.
Partner: UNT College of Arts and Sciences

Reactions of a Ru(II) Phenyl Complex with Substrates that Possess C-N or C-O Multiple Bonds: C-C Bond Formation, N-H Bond Cleavage, and Decarbonylation Reactions

Description: Article on the reactions of an Ru(II) phenyl complex with substrates that possess C-N or C-O multiple bonds and C-C bond formation, N-H bond cleavage, and decarbonylation reactions.
Date: February 8, 2006
Creator: Lee, John P.; Pittard, Karl A.; DeYonker, Nathan J.; Cundari, Thomas R., 1964-; Gunnoe, T. Brent & Petersen, Jeffrey L.
Partner: UNT College of Arts and Sciences

Combined Experimental and Computational Study of TpRu{P(pyr)3} (NCMe)Me (pyr = N-pyrrolyl): Inter- and Intramolecular Activation of C-H Bonds and the Impact of Sterics on Catalytic Hydroarylation of Olefins

Description: This article discusses a combined experimental and computational study of TpRu{P(pyr)3} (NCMe)Me (pyr = N-pyrrolyl).
Date: October 4, 2007
Creator: Foley, Nicholas A.; Lail, Marty; Gunnoe, T. Brent; Cundari, Thomas R., 1964-; Boyle, Paul D. & Petersen, Jeffrey L.
Partner: UNT College of Arts and Sciences

Platinum(II)-Catalyzed Ethylene Hydrophenylation: Switching Selectivity between Alkyl- and Vinylbenzene Production

Description: Article discussing platinum(II)-catalyzed ethylene hydrophenylation and the influence of dipyridyl chelate ring size on catalyst activity and longevity.
Date: April 23, 2013
Creator: McKeown, Bradley A.; Gonzalez, Hector Emanuel; Friedfeld, Max R.; Brosnahan, Anna M.; Gunnoe, T. Brent; Cundari, Thomas R., 1964- et al.
Partner: UNT College of Arts and Sciences