{"id":{"repo_id":"uiuc","oai_identifier":"oai:www.ideals.illinois.edu:2142/21304"},"canonical_url":"https://search.dev.ndltd.org/etd/uiuc/oai:www.ideals.illinois.edu:2142/21304","repository":{"repo_id":"uiuc","name":"University of Illinois - Urbana-Champaign","base_url":"https://www.ideals.illinois.edu/oai-pmh"},"display":{"title":"Approaches to the study of the geometry and mechanism of nucleophilic reactions at sulfur(II)","abstract":"Approaches to the study of the required reaction trajectory and geometry of nucleophilic attack at two different sulfur(II) species is reported. Systems designed to investigate the reaction trajectory involving nucleophilic attack at sulfur(II) by use of the endocyclic restriction test are discussed.","abstract_html":"Approaches to the study of the required reaction trajectory and geometry of nucleophilic attack at two different sulfur(II) species is reported. Systems designed to investigate the reaction trajectory involving nucleophilic attack at sulfur(II) by use of the endocyclic restriction test are discussed.","abstract_has_math":false,"creators":["Reif, Lee Alvin, Jr."],"institution":"University of Illinois at Urbana-Champaign","degree_name":"Ph.D.","degree_level":"Dissertation","degree_discipline":"Chemistry","degree_department":null,"school":null,"contributors":["Beak, Peter"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2011,"date_issued":"2011-05-07T13:04:43Z","date_published":"2011-05-07T13:04:43Z","updated_at":"2026-07-22T22:25:17Z","subjects":["Chemistry, Organic"],"languages":["eng"],"rights":["Copyright 1991 Reif, Lee Alvin, Jr"],"rights_urls":[],"identifier_entries":[{"key":"dc:identifier","label":"Identifier","values":["(UMI)AAI9136710","AAI9136710"],"render_values":[{"text":"(UMI)AAI9136710","href":null,"code":true},{"text":"AAI9136710","href":null,"code":true}]}]},"links":{"outbound_url":"http://hdl.handle.net/2142/21304","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Beak, Peter"]},{"key":"dc:creator","label":"Author","values":["Reif, Lee Alvin, Jr."]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2011-05-07T13:04:43Z","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, Organic"]}]},{"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 Reif, Lee Alvin, Jr"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["(UMI)AAI9136710","http://hdl.handle.net/2142/21304","AAI9136710"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Approaches to the study of the required reaction trajectory and geometry of nucleophilic attack at two different sulfur(II) species is reported. Systems designed to investigate the reaction trajectory involving nucleophilic attack at sulfur(II) by use of the endocyclic restriction test are discussed.","Treatment of 2-iodoaryldithioesters, 150 and 170, with tert-butyllithium provide, by halogen-lithium exchange, a reactive intermediate which adds carbophilically to the thiocarbonyl group generating indanone products, 161, 177, and 178. It was demonstrated that a phenyl anion would add thiophilically with these systems therefore suggesting that the required reaction trajectory for thiophilic addition could not be obtained in the formation of a six-membered ring. This reaction appears to provide the first evidence that a required reaction geometry exists for a thiophilic addition process. Formation of the indanone products provides evidence against the involvement of a radical process in thiophilic addition. It is reasonable to assume that if a radical is involved, it would close to the six-membered ring in our system. This was not observed, suggesting that a single electron process is unlikely.","A system, 198, containing a protected amine and a sulfenate was developed which may allow the study of the reaction geometry involved in nucleophilic substitution at bivalent sulfur. It was demonstrated that cleavage of the protecting group on the amine lead to conversion of the sulfenate to the sulfenamide, 199. Double labelling crossover studies were carried out with this system. Conditions could not be found for the deprotection of the amine which did not lead to scrambling of the sulfenamide product. Dilution studies with this system did not provide a clear choice between an intermolecular or intramolecular process. A by-product, 200, which arises from an intermolecular reaction is formed while the amount of sulfenamide product, 199, generated relative to starting material conversion, showed no change upon dilution suggesting an intramolecular process. No clear conclusion could be drawn on the bivalent sulfur system.","Made available in DSpace on 2011-05-07T13:04:43Z (GMT). No. of bitstreams: 2 license.txt: 4922 bytes, checksum: 910b249b4beec47e7ab768910c8f966f (MD5) 9136710.pdf: 5532505 bytes, checksum: cdb79498f9a0d12aaf2fce865b5b4080 (MD5) Previous issue date: 1991","Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Howard Ding (hding2@illinois.edu) on 2011-05-07T14:49:52Z Item is restricted indefinitely.","Restriction data tranferred 2014-07-01T11:22:43-05:00 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":["Approaches to the study of the geometry and mechanism of nucleophilic reactions at sulfur(II)"]}]}],"canonical_facts":{"dc:contributor":["Beak, Peter"],"dc:creator":["Reif, Lee Alvin, Jr."],"dc:date":["2011-05-07T13:04:43Z","10000-01-01","1991"],"dc:description":["Approaches to the study of the required reaction trajectory and geometry of nucleophilic attack at two different sulfur(II) species is reported. Systems designed to investigate the reaction trajectory involving nucleophilic attack at sulfur(II) by use of the endocyclic restriction test are discussed.","Treatment of 2-iodoaryldithioesters, 150 and 170, with tert-butyllithium provide, by halogen-lithium exchange, a reactive intermediate which adds carbophilically to the thiocarbonyl group generating indanone products, 161, 177, and 178. It was demonstrated that a phenyl anion would add thiophilically with these systems therefore suggesting that the required reaction trajectory for thiophilic addition could not be obtained in the formation of a six-membered ring. This reaction appears to provide the first evidence that a required reaction geometry exists for a thiophilic addition process. Formation of the indanone products provides evidence against the involvement of a radical process in thiophilic addition. It is reasonable to assume that if a radical is involved, it would close to the six-membered ring in our system. This was not observed, suggesting that a single electron process is unlikely.","A system, 198, containing a protected amine and a sulfenate was developed which may allow the study of the reaction geometry involved in nucleophilic substitution at bivalent sulfur. It was demonstrated that cleavage of the protecting group on the amine lead to conversion of the sulfenate to the sulfenamide, 199. Double labelling crossover studies were carried out with this system. Conditions could not be found for the deprotection of the amine which did not lead to scrambling of the sulfenamide product. Dilution studies with this system did not provide a clear choice between an intermolecular or intramolecular process. A by-product, 200, which arises from an intermolecular reaction is formed while the amount of sulfenamide product, 199, generated relative to starting material conversion, showed no change upon dilution suggesting an intramolecular process. No clear conclusion could be drawn on the bivalent sulfur system.","Made available in DSpace on 2011-05-07T13:04:43Z (GMT). No. of bitstreams: 2 license.txt: 4922 bytes, checksum: 910b249b4beec47e7ab768910c8f966f (MD5) 9136710.pdf: 5532505 bytes, checksum: cdb79498f9a0d12aaf2fce865b5b4080 (MD5) Previous issue date: 1991","Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Howard Ding (hding2@illinois.edu) on 2011-05-07T14:49:52Z Item is restricted indefinitely.","Restriction data tranferred 2014-07-01T11:22:43-05:00 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":["(UMI)AAI9136710","http://hdl.handle.net/2142/21304","AAI9136710"],"dc:language":["eng"],"dc:rights":["Copyright 1991 Reif, Lee Alvin, Jr"],"dc:subject":["Chemistry, Organic"],"dc:title":["Approaches to the study of the geometry and mechanism of nucleophilic reactions at sulfur(II)"],"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":"2026-07-22T22:25:17Z"}