{"id":{"repo_id":"uiuc","oai_identifier":"oai:www.ideals.illinois.edu:2142/20881"},"canonical_url":"https://search.dev.ndltd.org/etd/uiuc/oai:www.ideals.illinois.edu:2142/20881","repository":{"repo_id":"uiuc","name":"University of Illinois - Urbana-Champaign","base_url":"https://www.ideals.illinois.edu/oai-pmh"},"display":{"title":"The 'Indenyl Effect' in iridium(I) olefin complexes","abstract":"\"The complexes CpIr($\\eta\\sp2$-C$\\sb8$H$\\sb{14}$)CO and ($\\eta\\sp5$-C$\\sb9$H$\\sb7$)Ir($\\eta\\sp2$-C$\\sb8$H$\\sb{14}$)CO were prepared in high yield from (($\\eta\\sp2$-C$\\sb8$H$\\sb{14}$)$\\sb2$Ir(CO)Cl) $\\sb2$ and thallium cyclopentadienide or potassium indenide, respectively. The stereoisomers of CpIr($\\eta\\sp2$-C$\\sb8$H$\\sb{14}$)CO, ($\\eta\\sp5$-C$\\sb9$H$\\sb7$)Ir($\\eta\\sp2$-C$\\sb8$H$\\sb{14}$)CO, and ($\\eta\\sp5$-C$\\sb9$H$\\sb7$)Ir($\\eta\\sp2$-C$\\sb8$H$\\sb{14}$)$\\sb2$, were characterized by two-dimensional NMR techniques. Due to the \"\"Indenyl Effect,\"\" ($\\eta\\sp5$-C$\\sb9$H$\\sb7$)Ir($\\eta\\sp2$-C$\\sb8$H$\\sb{14}$)CO was more reactive than CpIr($\\eta\\sp2$-C$\\sb8$H$\\sb{14}$)CO toward Lewis bases. The labile cyclooctene ring of ($\\eta\\sp5$-C$\\sb9$H$\\sb7$)Ir($\\eta\\sp2$-C$\\sb8$H$\\sb{14}$)CO was readily replaced under mild conditions by other two electron donors such as triphenylphosphine, carbon monoxide, ethylene, or phenylacetylene; CpIr($\\eta\\sp2$-C$\\sb8$H$\\sb{14}$)CO was not reactive under identical or more severe conditions. The complex ($\\eta\\sp5$-C$\\sb9$H$\\sb7$)Ir($\\eta\\sp2$-C$\\sb8$H$\\sb{14}$)CO readily oxidatively added C-Br and Si-H bonds, again under mild conditions, and was found to be an active and robust catalyst for the hydrogenation and hydrosilylation of alkenes and alkynes. The reaction of CO with ($\\eta\\sp5$-C$\\sb9$H$\\sb7$)Ir(CO)$\\sb2$ resulted in the formation of the $\\eta\\sp1$-slipped indenyl ring of ($\\eta\\sp1$-C$\\sb9$H$\\sb7$)Ir(CO)$\\sb3$.\"","abstract_html":""The complexes CpIr($\\eta\\sp2$-C$\\sb8$H$\\sb{14}$)CO and ($\\eta\\sp5$-C$\\sb9$H$\\sb7$)Ir($\\eta\\sp2$-C$\\sb8$H$\\sb{14}$)CO were prepared in high yield from (($\\eta\\sp2$-C$\\sb8$H$\\sb{14}$)$\\sb2$Ir(CO)Cl) $\\sb2$ and thallium cyclopentadienide or potassium indenide, respectively. The stereoisomers of CpIr($\\eta\\sp2$-C$\\sb8$H$\\sb{14}$)CO, ($\\eta\\sp5$-C$\\sb9$H$\\sb7$)Ir($\\eta\\sp2$-C$\\sb8$H$\\sb{14}$)CO, and ($\\eta\\sp5$-C$\\sb9$H$\\sb7$)Ir($\\eta\\sp2$-C$\\sb8$H$\\sb{14}$)$\\sb2$, were characterized by two-dimensional NMR techniques. Due to the ""Indenyl Effect,"" ($\\eta\\sp5$-C$\\sb9$H$\\sb7$)Ir($\\eta\\sp2$-C$\\sb8$H$\\sb{14}$)CO was more reactive than CpIr($\\eta\\sp2$-C$\\sb8$H$\\sb{14}$)CO toward Lewis bases. The labile cyclooctene ring of ($\\eta\\sp5$-C$\\sb9$H$\\sb7$)Ir($\\eta\\sp2$-C$\\sb8$H$\\sb{14}$)CO was readily replaced under mild conditions by other two electron donors such as triphenylphosphine, carbon monoxide, ethylene, or phenylacetylene; CpIr($\\eta\\sp2$-C$\\sb8$H$\\sb{14}$)CO was not reactive under identical or more severe conditions. The complex ($\\eta\\sp5$-C$\\sb9$H$\\sb7$)Ir($\\eta\\sp2$-C$\\sb8$H$\\sb{14}$)CO readily oxidatively added C-Br and Si-H bonds, again under mild conditions, and was found to be an active and robust catalyst for the hydrogenation and hydrosilylation of alkenes and alkynes. The reaction of CO with ($\\eta\\sp5$-C$\\sb9$H$\\sb7$)Ir(CO)$\\sb2$ resulted in the formation of the $\\eta\\sp1$-slipped indenyl ring of ($\\eta\\sp1$-C$\\sb9$H$\\sb7$)Ir(CO)$\\sb3$."","abstract_has_math":true,"creators":["Szajek, Lawrence Philip"],"institution":"University of Illinois at Urbana-Champaign","degree_name":"Ph.D.","degree_level":"Dissertation","degree_discipline":"Chemistry","degree_department":null,"school":null,"contributors":["Shapley, John R."],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2011,"date_issued":"2011-05-07T12:51:59Z","date_published":"2011-05-07T12:51:59Z","updated_at":"2026-07-22T22:25:16Z","subjects":["Chemistry, Inorganic"],"languages":["eng"],"rights":["Copyright 1991 Szajek, Lawrence Philip"],"rights_urls":[],"identifier_entries":[{"key":"dc:identifier","label":"Identifier","values":["AAI9211007","(UMI)AAI9211007"],"render_values":[{"text":"AAI9211007","href":null,"code":true},{"text":"(UMI)AAI9211007","href":null,"code":true}]}]},"links":{"outbound_url":"http://hdl.handle.net/2142/20881","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Shapley, John R."]},{"key":"dc:creator","label":"Author","values":["Szajek, Lawrence Philip"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2011-05-07T12:51:59Z","10000-01-01","1991"]},{"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 1991 Szajek, Lawrence Philip"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["AAI9211007","(UMI)AAI9211007","http://hdl.handle.net/2142/20881"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["\"The complexes CpIr($\\eta\\sp2$-C$\\sb8$H$\\sb{14}$)CO and ($\\eta\\sp5$-C$\\sb9$H$\\sb7$)Ir($\\eta\\sp2$-C$\\sb8$H$\\sb{14}$)CO were prepared in high yield from (($\\eta\\sp2$-C$\\sb8$H$\\sb{14}$)$\\sb2$Ir(CO)Cl) $\\sb2$ and thallium cyclopentadienide or potassium indenide, respectively. The stereoisomers of CpIr($\\eta\\sp2$-C$\\sb8$H$\\sb{14}$)CO, ($\\eta\\sp5$-C$\\sb9$H$\\sb7$)Ir($\\eta\\sp2$-C$\\sb8$H$\\sb{14}$)CO, and ($\\eta\\sp5$-C$\\sb9$H$\\sb7$)Ir($\\eta\\sp2$-C$\\sb8$H$\\sb{14}$)$\\sb2$, were characterized by two-dimensional NMR techniques. Due to the \"\"Indenyl Effect,\"\" ($\\eta\\sp5$-C$\\sb9$H$\\sb7$)Ir($\\eta\\sp2$-C$\\sb8$H$\\sb{14}$)CO was more reactive than CpIr($\\eta\\sp2$-C$\\sb8$H$\\sb{14}$)CO toward Lewis bases. The labile cyclooctene ring of ($\\eta\\sp5$-C$\\sb9$H$\\sb7$)Ir($\\eta\\sp2$-C$\\sb8$H$\\sb{14}$)CO was readily replaced under mild conditions by other two electron donors such as triphenylphosphine, carbon monoxide, ethylene, or phenylacetylene; CpIr($\\eta\\sp2$-C$\\sb8$H$\\sb{14}$)CO was not reactive under identical or more severe conditions. The complex ($\\eta\\sp5$-C$\\sb9$H$\\sb7$)Ir($\\eta\\sp2$-C$\\sb8$H$\\sb{14}$)CO readily oxidatively added C-Br and Si-H bonds, again under mild conditions, and was found to be an active and robust catalyst for the hydrogenation and hydrosilylation of alkenes and alkynes. The reaction of CO with ($\\eta\\sp5$-C$\\sb9$H$\\sb7$)Ir(CO)$\\sb2$ resulted in the formation of the $\\eta\\sp1$-slipped indenyl ring of ($\\eta\\sp1$-C$\\sb9$H$\\sb7$)Ir(CO)$\\sb3$.\"","\"For CpIr($\\eta\\sp2$-C$\\sb2$H$\\sb4$)L and ($\\eta\\sp5$-C$\\sb9$H$\\sb7$)Ir($\\eta\\sp2$-C$\\sb2$H$\\sb4$)L, where L = ethylene or CO, the barrier to ethylene rotation about the iridium-ethylene bond axis was determined by lineshape fitting of variable-temperature $\\sp1$H NMR spectra. The free energies of activation were found to be 5-6 kcal/mole less for the indenyl complexes than for the corresponding cyclopentadienyl complexes (14 and 20 kcal/mole, respectively). This lowering of the barrier to ethylene rotation is an attribute of the \"\"Indenyl Effect.\"\"\"","Some related projects included the following. Attempted preparation of CpIr($\\eta\\sp2$-C$\\sb8$H$\\sb{14}$)$\\sb2$ resulted in an unexpected but useful synthesis of the cyclopentadiene complex CpIr($\\eta\\sp4$-C$\\sb5$H$\\sb6$). The proton and carbon resonances of the series of complexes CpM($\\eta\\sp4$-C$\\sb5$H$\\sb6$), where M = Co, Rh, or Ir, were compared. Protonation studies of CpIr($\\eta\\sp2$-C$\\sb8$H$\\sb{12}$) and ($\\eta\\sp5$-C$\\sb9$H$\\sb7$)Ir($\\eta\\sp2$-C$\\sb8$H$\\sb{12}$) allowed us to examine $\\eta\\sp5$ to $\\eta\\sp6$ haptotropic indenyl ring shifts. Synthetic routes to a metal cyclopentaphenanthrene complex Cp*Ru($\\eta\\sp5$-C$\\sb{15}$H$\\sb9$), were explored.","Made available in DSpace on 2011-05-07T12:51:59Z (GMT). No. of bitstreams: 2 license.txt: 4922 bytes, checksum: 910b249b4beec47e7ab768910c8f966f (MD5) 9211007.pdf: 5694377 bytes, checksum: ac76acfe70837b1cfbeaddae6456a173 (MD5) Previous issue date: 1991","Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Howard Ding (hding2@illinois.edu) on 2011-05-07T14:46:55Z Item is restricted indefinitely.","Restriction data tranferred 2014-07-01T11:21:07-05:00 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":["The 'Indenyl Effect' in iridium(I) olefin complexes"]}]}],"canonical_facts":{"dc:contributor":["Shapley, John R."],"dc:creator":["Szajek, Lawrence Philip"],"dc:date":["2011-05-07T12:51:59Z","10000-01-01","1991"],"dc:description":["\"The complexes CpIr($\\eta\\sp2$-C$\\sb8$H$\\sb{14}$)CO and ($\\eta\\sp5$-C$\\sb9$H$\\sb7$)Ir($\\eta\\sp2$-C$\\sb8$H$\\sb{14}$)CO were prepared in high yield from (($\\eta\\sp2$-C$\\sb8$H$\\sb{14}$)$\\sb2$Ir(CO)Cl) $\\sb2$ and thallium cyclopentadienide or potassium indenide, respectively. The stereoisomers of CpIr($\\eta\\sp2$-C$\\sb8$H$\\sb{14}$)CO, ($\\eta\\sp5$-C$\\sb9$H$\\sb7$)Ir($\\eta\\sp2$-C$\\sb8$H$\\sb{14}$)CO, and ($\\eta\\sp5$-C$\\sb9$H$\\sb7$)Ir($\\eta\\sp2$-C$\\sb8$H$\\sb{14}$)$\\sb2$, were characterized by two-dimensional NMR techniques. Due to the \"\"Indenyl Effect,\"\" ($\\eta\\sp5$-C$\\sb9$H$\\sb7$)Ir($\\eta\\sp2$-C$\\sb8$H$\\sb{14}$)CO was more reactive than CpIr($\\eta\\sp2$-C$\\sb8$H$\\sb{14}$)CO toward Lewis bases. The labile cyclooctene ring of ($\\eta\\sp5$-C$\\sb9$H$\\sb7$)Ir($\\eta\\sp2$-C$\\sb8$H$\\sb{14}$)CO was readily replaced under mild conditions by other two electron donors such as triphenylphosphine, carbon monoxide, ethylene, or phenylacetylene; CpIr($\\eta\\sp2$-C$\\sb8$H$\\sb{14}$)CO was not reactive under identical or more severe conditions. The complex ($\\eta\\sp5$-C$\\sb9$H$\\sb7$)Ir($\\eta\\sp2$-C$\\sb8$H$\\sb{14}$)CO readily oxidatively added C-Br and Si-H bonds, again under mild conditions, and was found to be an active and robust catalyst for the hydrogenation and hydrosilylation of alkenes and alkynes. The reaction of CO with ($\\eta\\sp5$-C$\\sb9$H$\\sb7$)Ir(CO)$\\sb2$ resulted in the formation of the $\\eta\\sp1$-slipped indenyl ring of ($\\eta\\sp1$-C$\\sb9$H$\\sb7$)Ir(CO)$\\sb3$.\"","\"For CpIr($\\eta\\sp2$-C$\\sb2$H$\\sb4$)L and ($\\eta\\sp5$-C$\\sb9$H$\\sb7$)Ir($\\eta\\sp2$-C$\\sb2$H$\\sb4$)L, where L = ethylene or CO, the barrier to ethylene rotation about the iridium-ethylene bond axis was determined by lineshape fitting of variable-temperature $\\sp1$H NMR spectra. The free energies of activation were found to be 5-6 kcal/mole less for the indenyl complexes than for the corresponding cyclopentadienyl complexes (14 and 20 kcal/mole, respectively). This lowering of the barrier to ethylene rotation is an attribute of the \"\"Indenyl Effect.\"\"\"","Some related projects included the following. Attempted preparation of CpIr($\\eta\\sp2$-C$\\sb8$H$\\sb{14}$)$\\sb2$ resulted in an unexpected but useful synthesis of the cyclopentadiene complex CpIr($\\eta\\sp4$-C$\\sb5$H$\\sb6$). The proton and carbon resonances of the series of complexes CpM($\\eta\\sp4$-C$\\sb5$H$\\sb6$), where M = Co, Rh, or Ir, were compared. Protonation studies of CpIr($\\eta\\sp2$-C$\\sb8$H$\\sb{12}$) and ($\\eta\\sp5$-C$\\sb9$H$\\sb7$)Ir($\\eta\\sp2$-C$\\sb8$H$\\sb{12}$) allowed us to examine $\\eta\\sp5$ to $\\eta\\sp6$ haptotropic indenyl ring shifts. Synthetic routes to a metal cyclopentaphenanthrene complex Cp*Ru($\\eta\\sp5$-C$\\sb{15}$H$\\sb9$), were explored.","Made available in DSpace on 2011-05-07T12:51:59Z (GMT). No. of bitstreams: 2 license.txt: 4922 bytes, checksum: 910b249b4beec47e7ab768910c8f966f (MD5) 9211007.pdf: 5694377 bytes, checksum: ac76acfe70837b1cfbeaddae6456a173 (MD5) Previous issue date: 1991","Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Howard Ding (hding2@illinois.edu) on 2011-05-07T14:46:55Z Item is restricted indefinitely.","Restriction data tranferred 2014-07-01T11:21:07-05:00 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":["AAI9211007","(UMI)AAI9211007","http://hdl.handle.net/2142/20881"],"dc:language":["eng"],"dc:rights":["Copyright 1991 Szajek, Lawrence Philip"],"dc:subject":["Chemistry, Inorganic"],"dc:title":["The 'Indenyl Effect' in iridium(I) olefin complexes"],"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":"2026-07-22T22:25:16Z"}