{"id":{"repo_id":"ubc","oai_identifier":"oai:circle.library.ubc.ca:2429/1299"},"canonical_url":"https://search.dev.ndltd.org/etd/ubc/oai:circle.library.ubc.ca:2429/1299","repository":{"repo_id":"ubc","name":"University of British Columbia","base_url":"http://circle.library.ubc.ca/oai/request"},"display":{"title":"Reversible binding of dihydrogen to dinuclear ruthenium complexes containing chelating diphosphines","abstract":"The preparation of dinuclear mixed-valence ruthenium complexes of general formula Ru₂Cl₅(P-P)₂, previously reported for a range of chelating ditertiary phosphines including chiral systems, has been extended to include compounds of the diphosphine 1,4-bis(dicyclohexylphosphino)butane (P-P = DCYPB). The complexes are generally prepared by the reaction of RuCl₃(PR₃)₂(DMA)‧DMA, R = phenyl or p-tolyl, DMA = N,N-dimethylacetamide, with one equilvalent of the appropriate diphosphine. The H₂-reduction of Ru₂Cl₅(P-P)₂ complexes in DMA, or in toluene in the presence of an added base, generally gives the dinuclear Ru(II,II) complexes [RuCl(P-P)(μ-Cl)]₂, but the DCYPB species was not formed; the procedures with DCYPB (including studies in CH₂Cl₂) led to poorly characterised complexes which may be polynuclear polyhydrides and appear to contain an η²-H₂ ligand. ¹H and ³¹P{¹H}NMR spectroscopy was used extensively to study the systems. The previously reported reaction of the dinuclear ruthenium(II) complex, [RuCl(DPPB)(μ-Cl)]₂ (DPPB = 1,4-bis(diphenylphosphino)butane), with 1 atm H₂ at ambient temperature to give the molecular hydrogen complex (η²-H₂)Ru(DPPB)(μ-Cl)₃RuCl(DPPB), has been extend to the 1,3-bis(diphenylphosphino)propane (DPPP) system; a corresponding η²-H₂ species with the DCYPB ligand has been detected following reaction of Ru₂Cl₅(DCYPB)₂ with H₂. The η²-H₂ ligands in the DPPP and DCYPB systems have internuclear distances of 0.86 Å as estimated by ¹H NMR variable temperature spin-lattice relaxation data (T₁(min) = 12 ms at 300 MHz). With the DPPP system, a ¹JHD of 29.4 Hz was found for the η²-HD isotopomer, and the η²-H₂ ligand is replaceable by N₂. The reversible equilibrium conversion under H₂ of [RuCl(DPPB)₂(μ-Cl)]₂, 9, to (η²-H₂)Ru(DPPB)(μ-Cl)₃RuCl(DPPB), 9a , in CH₂Cl₂ has been studied at 0-25°C by UV-vis and ³¹P{¹H}NMR spectroscopy, and by stopped-flow kinetics; the equilibrium constant and the corresponding thermodynamic parameters, and the forward and reverse rate constants have been determined. The equilibrium is close to being thermally neutral (ΔH° ~ zero), while a ΔS° value of ~60 J/mol K indicates the involvement of solvent molecules. A rough estimate of -60 kJ/mol is made for ΔH° of the process RuII + H₂ → RuII(η²-H₂). Preliminary studies were made on the reaction of [RuCl(DPPB)₂(μ-Cl)]₂, 9, with O₂, which may give a peroxide, and the subsequent reaction of this product with H₂; the latter reaction results in the formation of water and regeneration of a mixture of 9 and 9a.","abstract_html":"The preparation of dinuclear mixed-valence ruthenium complexes of general formula Ru₂Cl₅(P-P)₂, previously reported for a range of chelating ditertiary phosphines including chiral systems, has been extended to include compounds of the diphosphine 1,4-bis(dicyclohexylphosphino)butane (P-P = DCYPB). The complexes are generally prepared by the reaction of RuCl₃(PR₃)₂(DMA)‧DMA, R = phenyl or p-tolyl, DMA = N,N-dimethylacetamide, with one equilvalent of the appropriate diphosphine. The H₂-reduction of Ru₂Cl₅(P-P)₂ complexes in DMA, or in toluene in the presence of an added base, generally gives the dinuclear Ru(II,II) complexes [RuCl(P-P)(μ-Cl)]₂, but the DCYPB species was not formed; the procedures with DCYPB (including studies in CH₂Cl₂) led to poorly characterised complexes which may be polynuclear polyhydrides and appear to contain an η²-H₂ ligand. ¹H and ³¹P{¹H}NMR spectroscopy was used extensively to study the systems. The previously reported reaction of the dinuclear ruthenium(II) complex, [RuCl(DPPB)(μ-Cl)]₂ (DPPB = 1,4-bis(diphenylphosphino)butane), with 1 atm H₂ at ambient temperature to give the molecular hydrogen complex (η²-H₂)Ru(DPPB)(μ-Cl)₃RuCl(DPPB), has been extend to the 1,3-bis(diphenylphosphino)propane (DPPP) system; a corresponding η²-H₂ species with the DCYPB ligand has been detected following reaction of Ru₂Cl₅(DCYPB)₂ with H₂. The η²-H₂ ligands in the DPPP and DCYPB systems have internuclear distances of 0.86 Å as estimated by ¹H NMR variable temperature spin-lattice relaxation data (T₁(min) = 12 ms at 300 MHz). With the DPPP system, a ¹JHD of 29.4 Hz was found for the η²-HD isotopomer, and the η²-H₂ ligand is replaceable by N₂. The reversible equilibrium conversion under H₂ of [RuCl(DPPB)₂(μ-Cl)]₂, 9, to (η²-H₂)Ru(DPPB)(μ-Cl)₃RuCl(DPPB), 9a , in CH₂Cl₂ has been studied at 0-25°C by UV-vis and ³¹P{¹H}NMR spectroscopy, and by stopped-flow kinetics; the equilibrium constant and the corresponding thermodynamic parameters, and the forward and reverse rate constants have been determined. The equilibrium is close to being thermally neutral (ΔH° ~ zero), while a ΔS° value of ~60 J/mol K indicates the involvement of solvent molecules. A rough estimate of -60 kJ/mol is made for ΔH° of the process RuII + H₂ → RuII(η²-H₂). Preliminary studies were made on the reaction of [RuCl(DPPB)₂(μ-Cl)]₂, 9, with O₂, which may give a peroxide, and the subsequent reaction of this product with H₂; the latter reaction results in the formation of water and regeneration of a mixture of 9 and 9a.","abstract_has_math":false,"creators":["Chau, Daniel Elliot Kwok-Yue"],"institution":"University of British Columbia","degree_name":"Master of Science - MSc","degree_level":"master's","degree_discipline":"Chemistry","degree_department":null,"school":null,"contributors":[],"advisors":[],"committee_chairs":[],"committee_members":[],"year":1992,"date_issued":"1992","date_published":"1992","updated_at":"2026-07-24T05:07:15Z","subjects":[],"languages":["eng"],"rights":["For non-commercial purposes only, such as research, private study and education. Additional conditions apply, see Terms of Use https://open.library.ubc.ca/terms_of_use."],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"http://hdl.handle.net/2429/1299","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:creator","label":"Author","values":["Chau, Daniel Elliot Kwok-Yue"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["1992"]},{"key":"dc:publisher","label":"Institution","values":["University of British Columbia"]},{"key":"dc:type","label":"Dc Type","values":["Text"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Chemistry"]},{"key":"thesis:degree_level","label":"Degree Level","values":["master's"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Master of Science - MSc"]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["University of British Columbia"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["eng"]},{"key":"dc:rights","label":"Dc Rights","values":["For non-commercial purposes only, such as research, private study and education. Additional conditions apply, see Terms of Use https://open.library.ubc.ca/terms_of_use."]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["http://hdl.handle.net/2429/1299","http://circle.library.ubc.ca/bitstream/2429/1299/3/ubc_1993_spring_chau_daniel.pdf"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["The preparation of dinuclear mixed-valence ruthenium complexes of general formula Ru₂Cl₅(P-P)₂, previously reported for a range of chelating ditertiary phosphines including chiral systems, has been extended to include compounds of the diphosphine 1,4-bis(dicyclohexylphosphino)butane (P-P = DCYPB). The complexes are generally prepared by the reaction of RuCl₃(PR₃)₂(DMA)‧DMA, R = phenyl or p-tolyl, DMA = N,N-dimethylacetamide, with one equilvalent of the appropriate diphosphine. The H₂-reduction of Ru₂Cl₅(P-P)₂ complexes in DMA, or in toluene in the presence of an added base, generally gives the dinuclear Ru(II,II) complexes [RuCl(P-P)(μ-Cl)]₂, but the DCYPB species was not formed; the procedures with DCYPB (including studies in CH₂Cl₂) led to poorly characterised complexes which may be polynuclear polyhydrides and appear to contain an η²-H₂ ligand. ¹H and ³¹P{¹H}NMR spectroscopy was used extensively to study the systems. The previously reported reaction of the dinuclear ruthenium(II) complex, [RuCl(DPPB)(μ-Cl)]₂ (DPPB = 1,4-bis(diphenylphosphino)butane), with 1 atm H₂ at ambient temperature to give the molecular hydrogen complex (η²-H₂)Ru(DPPB)(μ-Cl)₃RuCl(DPPB), has been extend to the 1,3-bis(diphenylphosphino)propane (DPPP) system; a corresponding η²-H₂ species with the DCYPB ligand has been detected following reaction of Ru₂Cl₅(DCYPB)₂ with H₂. The η²-H₂ ligands in the DPPP and DCYPB systems have internuclear distances of 0.86 Å as estimated by ¹H NMR variable temperature spin-lattice relaxation data (T₁(min) = 12 ms at 300 MHz). With the DPPP system, a ¹JHD of 29.4 Hz was found for the η²-HD isotopomer, and the η²-H₂ ligand is replaceable by N₂. The reversible equilibrium conversion under H₂ of [RuCl(DPPB)₂(μ-Cl)]₂, 9, to (η²-H₂)Ru(DPPB)(μ-Cl)₃RuCl(DPPB), 9a , in CH₂Cl₂ has been studied at 0-25°C by UV-vis and ³¹P{¹H}NMR spectroscopy, and by stopped-flow kinetics; the equilibrium constant and the corresponding thermodynamic parameters, and the forward and reverse rate constants have been determined. The equilibrium is close to being thermally neutral (ΔH° ~ zero), while a ΔS° value of ~60 J/mol K indicates the involvement of solvent molecules. A rough estimate of -60 kJ/mol is made for ΔH° of the process RuII + H₂ → RuII(η²-H₂). Preliminary studies were made on the reaction of [RuCl(DPPB)₂(μ-Cl)]₂, 9, with O₂, which may give a peroxide, and the subsequent reaction of this product with H₂; the latter reaction results in the formation of water and regeneration of a mixture of 9 and 9a."]},{"key":"dc:format","label":"Dc Format","values":["5685595","application/pdf"]},{"key":"dc:title","label":"Title","values":["Reversible binding of dihydrogen to dinuclear ruthenium complexes containing chelating diphosphines"]}]}],"canonical_facts":{"dc:creator":["Chau, Daniel Elliot Kwok-Yue"],"dc:date":["1992"],"dc:description":["The preparation of dinuclear mixed-valence ruthenium complexes of general formula Ru₂Cl₅(P-P)₂, previously reported for a range of chelating ditertiary phosphines including chiral systems, has been extended to include compounds of the diphosphine 1,4-bis(dicyclohexylphosphino)butane (P-P = DCYPB). The complexes are generally prepared by the reaction of RuCl₃(PR₃)₂(DMA)‧DMA, R = phenyl or p-tolyl, DMA = N,N-dimethylacetamide, with one equilvalent of the appropriate diphosphine. The H₂-reduction of Ru₂Cl₅(P-P)₂ complexes in DMA, or in toluene in the presence of an added base, generally gives the dinuclear Ru(II,II) complexes [RuCl(P-P)(μ-Cl)]₂, but the DCYPB species was not formed; the procedures with DCYPB (including studies in CH₂Cl₂) led to poorly characterised complexes which may be polynuclear polyhydrides and appear to contain an η²-H₂ ligand. ¹H and ³¹P{¹H}NMR spectroscopy was used extensively to study the systems. The previously reported reaction of the dinuclear ruthenium(II) complex, [RuCl(DPPB)(μ-Cl)]₂ (DPPB = 1,4-bis(diphenylphosphino)butane), with 1 atm H₂ at ambient temperature to give the molecular hydrogen complex (η²-H₂)Ru(DPPB)(μ-Cl)₃RuCl(DPPB), has been extend to the 1,3-bis(diphenylphosphino)propane (DPPP) system; a corresponding η²-H₂ species with the DCYPB ligand has been detected following reaction of Ru₂Cl₅(DCYPB)₂ with H₂. The η²-H₂ ligands in the DPPP and DCYPB systems have internuclear distances of 0.86 Å as estimated by ¹H NMR variable temperature spin-lattice relaxation data (T₁(min) = 12 ms at 300 MHz). With the DPPP system, a ¹JHD of 29.4 Hz was found for the η²-HD isotopomer, and the η²-H₂ ligand is replaceable by N₂. The reversible equilibrium conversion under H₂ of [RuCl(DPPB)₂(μ-Cl)]₂, 9, to (η²-H₂)Ru(DPPB)(μ-Cl)₃RuCl(DPPB), 9a , in CH₂Cl₂ has been studied at 0-25°C by UV-vis and ³¹P{¹H}NMR spectroscopy, and by stopped-flow kinetics; the equilibrium constant and the corresponding thermodynamic parameters, and the forward and reverse rate constants have been determined. The equilibrium is close to being thermally neutral (ΔH° ~ zero), while a ΔS° value of ~60 J/mol K indicates the involvement of solvent molecules. A rough estimate of -60 kJ/mol is made for ΔH° of the process RuII + H₂ → RuII(η²-H₂). Preliminary studies were made on the reaction of [RuCl(DPPB)₂(μ-Cl)]₂, 9, with O₂, which may give a peroxide, and the subsequent reaction of this product with H₂; the latter reaction results in the formation of water and regeneration of a mixture of 9 and 9a."],"dc:format":["5685595","application/pdf"],"dc:identifier":["http://hdl.handle.net/2429/1299","http://circle.library.ubc.ca/bitstream/2429/1299/3/ubc_1993_spring_chau_daniel.pdf"],"dc:language":["eng"],"dc:publisher":["University of British Columbia"],"dc:rights":["For non-commercial purposes only, such as research, private study and education. Additional conditions apply, see Terms of Use https://open.library.ubc.ca/terms_of_use."],"dc:title":["Reversible binding of dihydrogen to dinuclear ruthenium complexes containing chelating diphosphines"],"dc:type":["Text"],"thesis:degree_discipline":["Chemistry"],"thesis:degree_level":["master's"],"thesis:degree_name":["Master of Science - MSc"],"thesis:institution_name":["University of British Columbia"]},"updated_at":"2026-07-24T05:07:15Z"}