{"id":{"repo_id":"uiuc","oai_identifier":"oai:www.ideals.illinois.edu:2142/23038"},"canonical_url":"https://search.dev.ndltd.org/etd/uiuc/oai:www.ideals.illinois.edu:2142/23038","repository":{"repo_id":"uiuc","name":"University of Illinois - Urbana-Champaign","base_url":"https://www.ideals.illinois.edu/oai-pmh"},"display":{"title":"Zirconium and hafnium organometallic compounds: Molecular geometry for five-, and seven-coordinate species","abstract":"Alkylation of ZrCl$\\sb4$ with phenyllithium affords the new d$\\sp0$ complex $\\rm\\lbrack Li(Et\\sb2O)\\rbrack\\sb2\\lbrack ZrPh\\sb6\\rbrack ;$ the $\\rm\\lbrack ZrPh\\sb6\\sp{2-}$) anion adopts a trigonal prismatic geometry. Despite the presence of orbitals on the phenyl ligands that are of the right symmetry to serve as $\\pi$-donors, the trigonal prismatic geometry clearly shows that the phenyl groups are not acting as $\\pi$-donors. The lithium cations form weak interactions with the ipso carbons of the phenyl rings.","abstract_html":"Alkylation of ZrCl$\\sb4$ with phenyllithium affords the new d$\\sp0$ complex $\\rm\\lbrack Li(Et\\sb2O)\\rbrack\\sb2\\lbrack ZrPh\\sb6\\rbrack ;$ the $\\rm\\lbrack ZrPh\\sb6\\sp{2-}$) anion adopts a trigonal prismatic geometry. Despite the presence of orbitals on the phenyl ligands that are of the right symmetry to serve as <span class=\"etd-inline-math\">&pi;</span>-donors, the trigonal prismatic geometry clearly shows that the phenyl groups are not acting as <span class=\"etd-inline-math\">&pi;</span>-donors. The lithium cations form weak interactions with the ipso carbons of the phenyl rings.","abstract_has_math":true,"creators":["Nelsen, Melissa Jane"],"institution":"University of Illinois at Urbana-Champaign","degree_name":"Ph.D.","degree_level":"Dissertation","degree_discipline":"Chemistry","degree_department":null,"school":null,"contributors":["Girolami, Gregory S."],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2011,"date_issued":"2011-05-07T13:59:56Z","date_published":"2011-05-07T13:59:56Z","updated_at":"2026-07-22T22:25:21Z","subjects":["Chemistry, Inorganic"],"languages":["eng"],"rights":["Copyright 1996 Nelsen, Melissa Jane"],"rights_urls":[],"identifier_entries":[{"key":"dc:identifier","label":"Identifier","values":["9780591198447","AAI9712387","(UMI)AAI9712387"],"render_values":[{"text":"9780591198447","href":null,"code":true},{"text":"AAI9712387","href":null,"code":true},{"text":"(UMI)AAI9712387","href":null,"code":true}]}]},"links":{"outbound_url":"http://hdl.handle.net/2142/23038","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Girolami, Gregory S."]},{"key":"dc:creator","label":"Author","values":["Nelsen, Melissa Jane"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2011-05-07T13:59:56Z","10000-01-01","1996"]},{"key":"dc:type","label":"Dc Type","values":["text"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Chemistry"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Dissertation"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Ph.D."]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["University of Illinois at Urbana-Champaign"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Chemistry, Inorganic"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["eng"]},{"key":"dc:rights","label":"Dc Rights","values":["Copyright 1996 Nelsen, Melissa Jane"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["9780591198447","AAI9712387","(UMI)AAI9712387","http://hdl.handle.net/2142/23038"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Alkylation of ZrCl$\\sb4$ with phenyllithium affords the new d$\\sp0$ complex $\\rm\\lbrack Li(Et\\sb2O)\\rbrack\\sb2\\lbrack ZrPh\\sb6\\rbrack ;$ the $\\rm\\lbrack ZrPh\\sb6\\sp{2-}$) anion adopts a trigonal prismatic geometry. Despite the presence of orbitals on the phenyl ligands that are of the right symmetry to serve as $\\pi$-donors, the trigonal prismatic geometry clearly shows that the phenyl groups are not acting as $\\pi$-donors. The lithium cations form weak interactions with the ipso carbons of the phenyl rings.","In an attempt to prepare six-coordinate d$\\sp0$ species that lack Li$\\sp\\cdots$C interactions, the synthesis of zirconium pentafluorophenyl complexes was investigated. The compounds (Li(12-crown-4)$\\rm\\sb2\\rbrack\\sb2\\lbrack ZrCl\\sb2(C\\sb6F\\sb5)\\sb4$) and $\\rm\\lbrack Li(tmed)\\sb2\\rbrack\\lbrack Li(tmed)\\rbrack\\sb2\\lbrack ZrF\\sb2(C\\sb6F\\sb5)\\sb5$) were isolated; the first adopts an octahedral structure owing to the $\\pi$-donor character of the chloride ligands, while the latter adopts a regular pentagonal bipyramidal structure. The latter compound also shows that C-F bond activation has occuned.","Alkylatidn of the phosphine complexes ZrCl$\\sb4$(PP) and HfCl$\\sb4$(PP) complexes with $\\rm LiCH\\sb2SiMe\\sb3$ affords unusual lithium salts of five-coordinate zirconium auryls; one of these salts, $\\rm\\lbrack Li(dcype)\\sb2\\rbrack\\lbrack Zr(CH\\sb2SiMe\\sb3)\\sb5$) where dcype is 1,2-bis(dicyclohexylphosphino)ethane, was structurally characterized. The structure of the anion is best described as a distorted square pyramid; the structure is consistent with molecular orbital calculations which predict that square pyramidal structures should be adopted for such d$\\sp0$ species. Equally interesting is the structure of the cation, which consists of a lithium atom surrounded by a distorted tetrahedral array of two diphosphine ligands. These results bear on important issues such as whether five-coordinate d$\\sp0$ alkyls are susceptible to Jahn-Teller distortions, and whether trialkylphosphine ligands should be classified as hard or soft Lewis bases.","Treatment of $\\rm (C\\sb8H\\sb8)ZrCl\\sb2(thf)\\sp{\\cdot}2KCl$ with one equivalent of p-tolyllithium, followed by the addition of $\\rm N,N,N\\sp\\prime ,N\\sp\\prime$-tetramethylethylenediamine (tmed), yields red crystals of the mono(p-tolyl) complex $\\rm\\lbrack Li(tmed)\\rbrack\\lbrack (C\\sb8H\\sb8)Zr(p$-$\\rm C\\sb6H\\sb4Me)Cl\\sb2$); this compound has been crystallographically characterized. Treatment of $\\rm (C\\sb8H\\sb8)MCl\\sb2{\\cdot}2KCl$ (M = Zr, Hf) with three equivalents of methyl-, phenyl-, or p-tolyllithium in tetrahydrofuran or diethyl ether, followed by addition of $\\rm N,N,N\\sp\\prime ,N\\sp\\prime$-tetramethyl-ethylenediamine, yields several new organozirconium and -hafnium compounds of stoichiometry $\\rm\\lbrack Li(tmed)\\sb2\\rbrack\\lbrack (C\\sb8H\\sb8)MR\\sb3$) where R = Me, Ph, or p-$\\rm C\\sb6H\\sb4Me$. With larger alkyl groups, electrically neutral organozirconium and -hafnium complexes can be isolated: treatment of $\\rm (C\\sb8H\\sb8)MCl\\sb2(thf)\\sp{\\cdot}2KCl$ with 2 equiv. of LiCH(SiMe$\\sb3)\\sb2$ gives products of stoichiometry $\\rm (C\\sb8H\\sb8)M\\lbrack CH(SiMe\\sb3)\\sb2\\rbrack\\sb2$. The structure of this latter complex has been determined. Interestingly, this latter 14-electron molecule reacts reversibly with carbon monoxide but is unaffected by dihydrogen even at elevated pressures.","Made available in DSpace on 2011-05-07T13:59:56Z (GMT). No. of bitstreams: 2 license.txt: 4922 bytes, checksum: 910b249b4beec47e7ab768910c8f966f (MD5) 9712387.pdf: 6244417 bytes, checksum: ad502ea8a2d134c23846bf3353b7b778 (MD5) Previous issue date: 1996","Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Howard Ding (hding2@illinois.edu) on 2011-05-07T15:01:45Z Item is restricted indefinitely.","Restriction data tranferred 2014-07-01T11:29:19-05:00 Original Data Group with Access UIUC Users [automated] Release Date: none Reason: ETDs are only available to UIUC Users without author permission","ETDs are only available to UIUC Users without author permission","U of I Only"]},{"key":"dc:title","label":"Title","values":["Zirconium and hafnium organometallic compounds: Molecular geometry for five-, and seven-coordinate species"]}]}],"canonical_facts":{"dc:contributor":["Girolami, Gregory S."],"dc:creator":["Nelsen, Melissa Jane"],"dc:date":["2011-05-07T13:59:56Z","10000-01-01","1996"],"dc:description":["Alkylation of ZrCl$\\sb4$ with phenyllithium affords the new d$\\sp0$ complex $\\rm\\lbrack Li(Et\\sb2O)\\rbrack\\sb2\\lbrack ZrPh\\sb6\\rbrack ;$ the $\\rm\\lbrack ZrPh\\sb6\\sp{2-}$) anion adopts a trigonal prismatic geometry. Despite the presence of orbitals on the phenyl ligands that are of the right symmetry to serve as $\\pi$-donors, the trigonal prismatic geometry clearly shows that the phenyl groups are not acting as $\\pi$-donors. The lithium cations form weak interactions with the ipso carbons of the phenyl rings.","In an attempt to prepare six-coordinate d$\\sp0$ species that lack Li$\\sp\\cdots$C interactions, the synthesis of zirconium pentafluorophenyl complexes was investigated. The compounds (Li(12-crown-4)$\\rm\\sb2\\rbrack\\sb2\\lbrack ZrCl\\sb2(C\\sb6F\\sb5)\\sb4$) and $\\rm\\lbrack Li(tmed)\\sb2\\rbrack\\lbrack Li(tmed)\\rbrack\\sb2\\lbrack ZrF\\sb2(C\\sb6F\\sb5)\\sb5$) were isolated; the first adopts an octahedral structure owing to the $\\pi$-donor character of the chloride ligands, while the latter adopts a regular pentagonal bipyramidal structure. The latter compound also shows that C-F bond activation has occuned.","Alkylatidn of the phosphine complexes ZrCl$\\sb4$(PP) and HfCl$\\sb4$(PP) complexes with $\\rm LiCH\\sb2SiMe\\sb3$ affords unusual lithium salts of five-coordinate zirconium auryls; one of these salts, $\\rm\\lbrack Li(dcype)\\sb2\\rbrack\\lbrack Zr(CH\\sb2SiMe\\sb3)\\sb5$) where dcype is 1,2-bis(dicyclohexylphosphino)ethane, was structurally characterized. The structure of the anion is best described as a distorted square pyramid; the structure is consistent with molecular orbital calculations which predict that square pyramidal structures should be adopted for such d$\\sp0$ species. Equally interesting is the structure of the cation, which consists of a lithium atom surrounded by a distorted tetrahedral array of two diphosphine ligands. These results bear on important issues such as whether five-coordinate d$\\sp0$ alkyls are susceptible to Jahn-Teller distortions, and whether trialkylphosphine ligands should be classified as hard or soft Lewis bases.","Treatment of $\\rm (C\\sb8H\\sb8)ZrCl\\sb2(thf)\\sp{\\cdot}2KCl$ with one equivalent of p-tolyllithium, followed by the addition of $\\rm N,N,N\\sp\\prime ,N\\sp\\prime$-tetramethylethylenediamine (tmed), yields red crystals of the mono(p-tolyl) complex $\\rm\\lbrack Li(tmed)\\rbrack\\lbrack (C\\sb8H\\sb8)Zr(p$-$\\rm C\\sb6H\\sb4Me)Cl\\sb2$); this compound has been crystallographically characterized. Treatment of $\\rm (C\\sb8H\\sb8)MCl\\sb2{\\cdot}2KCl$ (M = Zr, Hf) with three equivalents of methyl-, phenyl-, or p-tolyllithium in tetrahydrofuran or diethyl ether, followed by addition of $\\rm N,N,N\\sp\\prime ,N\\sp\\prime$-tetramethyl-ethylenediamine, yields several new organozirconium and -hafnium compounds of stoichiometry $\\rm\\lbrack Li(tmed)\\sb2\\rbrack\\lbrack (C\\sb8H\\sb8)MR\\sb3$) where R = Me, Ph, or p-$\\rm C\\sb6H\\sb4Me$. With larger alkyl groups, electrically neutral organozirconium and -hafnium complexes can be isolated: treatment of $\\rm (C\\sb8H\\sb8)MCl\\sb2(thf)\\sp{\\cdot}2KCl$ with 2 equiv. of LiCH(SiMe$\\sb3)\\sb2$ gives products of stoichiometry $\\rm (C\\sb8H\\sb8)M\\lbrack CH(SiMe\\sb3)\\sb2\\rbrack\\sb2$. The structure of this latter complex has been determined. Interestingly, this latter 14-electron molecule reacts reversibly with carbon monoxide but is unaffected by dihydrogen even at elevated pressures.","Made available in DSpace on 2011-05-07T13:59:56Z (GMT). No. of bitstreams: 2 license.txt: 4922 bytes, checksum: 910b249b4beec47e7ab768910c8f966f (MD5) 9712387.pdf: 6244417 bytes, checksum: ad502ea8a2d134c23846bf3353b7b778 (MD5) Previous issue date: 1996","Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Howard Ding (hding2@illinois.edu) on 2011-05-07T15:01:45Z Item is restricted indefinitely.","Restriction data tranferred 2014-07-01T11:29:19-05:00 Original Data Group with Access UIUC Users [automated] Release Date: none Reason: ETDs are only available to UIUC Users without author permission","ETDs are only available to UIUC Users without author permission","U of I Only"],"dc:identifier":["9780591198447","AAI9712387","(UMI)AAI9712387","http://hdl.handle.net/2142/23038"],"dc:language":["eng"],"dc:rights":["Copyright 1996 Nelsen, Melissa Jane"],"dc:subject":["Chemistry, Inorganic"],"dc:title":["Zirconium and hafnium organometallic compounds: Molecular geometry for five-, and seven-coordinate species"],"dc:type":["text"],"thesis:degree_discipline":["Chemistry"],"thesis:degree_level":["Dissertation"],"thesis:degree_name":["Ph.D."],"thesis:institution_name":["University of Illinois at Urbana-Champaign"]},"updated_at":"2026-07-22T22:25:21Z"}