{"id":{"repo_id":"uiuc","oai_identifier":"oai:www.ideals.illinois.edu:2142/70327"},"canonical_url":"https://search.dev.ndltd.org/etd/uiuc/oai:www.ideals.illinois.edu:2142/70327","repository":{"repo_id":"uiuc","name":"University of Illinois - Urbana-Champaign","base_url":"https://www.ideals.illinois.edu/oai-pmh"},"display":{"title":"Remote Lithiations of Carboxamides: The Manifestation of a Post-Complexation Proximity Effect (Homoenolate)","abstract":"The remote metalations of tertiary amides, (beta) and (gamma) substituted with vinyl, phenyl and thiophenol groups, are reported. N,N-Diisopropyl-2-methylpent-4-enecarboxamide (59), N,N-diisopropyl-2-methyl-3-phenylpropanecarboxamide (139), N,N-diisopropyl-2-methyl-3-phenylthiopropanecarboxamide (174), N,N-diisopropyl-2-methyl-3-phenylthiobutanecarboxamide (176), N,N-diisopropyl-3-phenylthio-2-(phenylthiomethyl)propanecarboxamide (215) and N,N-diisopropyl-2-methyl-3-phenylthio-2-(phenylthiomethyl)butanecarboxamide (217), undergo deprotonation at the (beta) position upon reaction with sec-BuLi/TMEDA. The intermediate benzyl and thiomethylene anions react with a variety of electrophiles to yield (beta) substituted products. In the case of 217, metalation and electrophilic substitution occurs at a (beta) secondary carbon atom. The allylic alkyllithium generated undergoes electrophilic at the (beta) or (delta) position. Lithiation and substitution at the (gamma) position occurs upon treatment of N,N-diisopropyl-2-methyl-4-phenylthiobutanecarboxamide (193), with sec-BuLi/TMEDA, followed by an electrophile. The synthetic consequences of the metalations are discussed and demonstrated.","abstract_html":"The remote metalations of tertiary amides, (beta) and (gamma) substituted with vinyl, phenyl and thiophenol groups, are reported. N,N-Diisopropyl-2-methylpent-4-enecarboxamide (59), N,N-diisopropyl-2-methyl-3-phenylpropanecarboxamide (139), N,N-diisopropyl-2-methyl-3-phenylthiopropanecarboxamide (174), N,N-diisopropyl-2-methyl-3-phenylthiobutanecarboxamide (176), N,N-diisopropyl-3-phenylthio-2-(phenylthiomethyl)propanecarboxamide (215) and N,N-diisopropyl-2-methyl-3-phenylthio-2-(phenylthiomethyl)butanecarboxamide (217), undergo deprotonation at the (beta) position upon reaction with sec-BuLi/TMEDA. The intermediate benzyl and thiomethylene anions react with a variety of electrophiles to yield (beta) substituted products. In the case of 217, metalation and electrophilic substitution occurs at a (beta) secondary carbon atom. The allylic alkyllithium generated undergoes electrophilic at the (beta) or (delta) position. Lithiation and substitution at the (gamma) position occurs upon treatment of N,N-diisopropyl-2-methyl-4-phenylthiobutanecarboxamide (193), with sec-BuLi/TMEDA, followed by an electrophile. The synthetic consequences of the metalations are discussed and demonstrated.","abstract_has_math":false,"creators":["Hunter, James Edward"],"institution":"University of Illinois at Urbana-Champaign","degree_name":"Ph.D.","degree_level":"Dissertation","degree_discipline":"Chemistry","degree_department":null,"school":null,"contributors":[],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2014,"date_issued":"2014-12-15T23:18:41Z","date_published":"2014-12-15T23:18:41Z","updated_at":"2026-07-22T22:26:02Z","subjects":["Chemistry, Organic"],"languages":[],"rights":[],"rights_urls":[],"identifier_entries":[{"key":"dc:identifier","label":"Identifier","values":["(UMI)AAI8623328"],"render_values":[{"text":"(UMI)AAI8623328","href":null,"code":true}]}]},"links":{"outbound_url":"http://hdl.handle.net/2142/70327","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:creator","label":"Author","values":["Hunter, James Edward"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2014-12-15T23:18:41Z","10000-01-01","1986"]},{"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":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["http://hdl.handle.net/2142/70327","(UMI)AAI8623328"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["The remote metalations of tertiary amides, (beta) and (gamma) substituted with vinyl, phenyl and thiophenol groups, are reported. N,N-Diisopropyl-2-methylpent-4-enecarboxamide (59), N,N-diisopropyl-2-methyl-3-phenylpropanecarboxamide (139), N,N-diisopropyl-2-methyl-3-phenylthiopropanecarboxamide (174), N,N-diisopropyl-2-methyl-3-phenylthiobutanecarboxamide (176), N,N-diisopropyl-3-phenylthio-2-(phenylthiomethyl)propanecarboxamide (215) and N,N-diisopropyl-2-methyl-3-phenylthio-2-(phenylthiomethyl)butanecarboxamide (217), undergo deprotonation at the (beta) position upon reaction with sec-BuLi/TMEDA. The intermediate benzyl and thiomethylene anions react with a variety of electrophiles to yield (beta) substituted products. In the case of 217, metalation and electrophilic substitution occurs at a (beta) secondary carbon atom. The allylic alkyllithium generated undergoes electrophilic at the (beta) or (delta) position. Lithiation and substitution at the (gamma) position occurs upon treatment of N,N-diisopropyl-2-methyl-4-phenylthiobutanecarboxamide (193), with sec-BuLi/TMEDA, followed by an electrophile. The synthetic consequences of the metalations are discussed and demonstrated.","The stereochemistry of electrophilic addition to the anion may be controlled in some cases. With the allyllithium from 59, preferential or exclusive (delta) substitution is observed. When magnesium is employed as the counterion only (delta) substitution is observed. In all (delta) addition products the olefin has a Z geometry. The benzyl anion of 139 reacts with electrophiles at -78 (DEGREES)C to give predominantly the R*,R* diastereoisomer. Greater selectivity towards the R*,R* isomer is achieved at higher reaction temperatures.","The mechanism of the remote metalation has been investigated. In the metalation of 59, 139, and 193 the (beta) anion is generated without initial or concurrent (alpha) proton abstraction. It was also shown that in DMSO, the (alpha) proton of N,N-diisopropylcyclohex-3-enecarboxamide (33), is thermodynamically more acidic than the (beta) proton. The amide functionality is postulated to promote (beta) and (gamma) metalation through its ability to coordinate sec-BuLi in a pre-equilibrium complex in which the butyl group is positioned to direct deprotonation at a proximate site.","Made available in DSpace on 2014-12-15T23:18:41Z (GMT). No. of bitstreams: 1 8623328.pdf: 6954228 bytes, checksum: 1a44ff589f848948fe18f8f7c4d0b61e (MD5) Previous issue date: 1986","Embargo set by: Seth Robbins for item 70493 Lift date: Forever Reason: Restricted to the U of I community idenfinitely during batch ingest of legacy ETDs","Restricted to the U of I community idenfinitely during batch ingest of legacy ETDs","U of I Only","192 p.","Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1986."]},{"key":"dc:title","label":"Title","values":["Remote Lithiations of Carboxamides: The Manifestation of a Post-Complexation Proximity Effect (Homoenolate)"]}]}],"canonical_facts":{"dc:creator":["Hunter, James Edward"],"dc:date":["2014-12-15T23:18:41Z","10000-01-01","1986"],"dc:description":["The remote metalations of tertiary amides, (beta) and (gamma) substituted with vinyl, phenyl and thiophenol groups, are reported. N,N-Diisopropyl-2-methylpent-4-enecarboxamide (59), N,N-diisopropyl-2-methyl-3-phenylpropanecarboxamide (139), N,N-diisopropyl-2-methyl-3-phenylthiopropanecarboxamide (174), N,N-diisopropyl-2-methyl-3-phenylthiobutanecarboxamide (176), N,N-diisopropyl-3-phenylthio-2-(phenylthiomethyl)propanecarboxamide (215) and N,N-diisopropyl-2-methyl-3-phenylthio-2-(phenylthiomethyl)butanecarboxamide (217), undergo deprotonation at the (beta) position upon reaction with sec-BuLi/TMEDA. The intermediate benzyl and thiomethylene anions react with a variety of electrophiles to yield (beta) substituted products. In the case of 217, metalation and electrophilic substitution occurs at a (beta) secondary carbon atom. The allylic alkyllithium generated undergoes electrophilic at the (beta) or (delta) position. Lithiation and substitution at the (gamma) position occurs upon treatment of N,N-diisopropyl-2-methyl-4-phenylthiobutanecarboxamide (193), with sec-BuLi/TMEDA, followed by an electrophile. The synthetic consequences of the metalations are discussed and demonstrated.","The stereochemistry of electrophilic addition to the anion may be controlled in some cases. With the allyllithium from 59, preferential or exclusive (delta) substitution is observed. When magnesium is employed as the counterion only (delta) substitution is observed. In all (delta) addition products the olefin has a Z geometry. The benzyl anion of 139 reacts with electrophiles at -78 (DEGREES)C to give predominantly the R*,R* diastereoisomer. Greater selectivity towards the R*,R* isomer is achieved at higher reaction temperatures.","The mechanism of the remote metalation has been investigated. In the metalation of 59, 139, and 193 the (beta) anion is generated without initial or concurrent (alpha) proton abstraction. It was also shown that in DMSO, the (alpha) proton of N,N-diisopropylcyclohex-3-enecarboxamide (33), is thermodynamically more acidic than the (beta) proton. The amide functionality is postulated to promote (beta) and (gamma) metalation through its ability to coordinate sec-BuLi in a pre-equilibrium complex in which the butyl group is positioned to direct deprotonation at a proximate site.","Made available in DSpace on 2014-12-15T23:18:41Z (GMT). No. of bitstreams: 1 8623328.pdf: 6954228 bytes, checksum: 1a44ff589f848948fe18f8f7c4d0b61e (MD5) Previous issue date: 1986","Embargo set by: Seth Robbins for item 70493 Lift date: Forever Reason: Restricted to the U of I community idenfinitely during batch ingest of legacy ETDs","Restricted to the U of I community idenfinitely during batch ingest of legacy ETDs","U of I Only","192 p.","Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1986."],"dc:identifier":["http://hdl.handle.net/2142/70327","(UMI)AAI8623328"],"dc:subject":["Chemistry, Organic"],"dc:title":["Remote Lithiations of Carboxamides: The Manifestation of a Post-Complexation Proximity Effect (Homoenolate)"],"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":"2026-07-22T22:26:02Z"}