{"id":{"repo_id":"uiuc","oai_identifier":"oai:www.ideals.illinois.edu:2142/72266"},"canonical_url":"https://search.dev.ndltd.org/etd/uiuc/oai:www.ideals.illinois.edu:2142/72266","repository":{"repo_id":"uiuc","name":"University of Illinois - Urbana-Champaign","base_url":"https://www.ideals.illinois.edu/oai-pmh"},"display":{"title":"Direction and Stabilization of Alpha' and Beta Metalations by Tertiary Carboxamides","abstract":"Metalations $\\alpha\\sp\\prime$ and $\\beta$ to a tertiary amide have been investigated. Control and understanding of the regiochemistry of these novel metalations is discussed.","abstract_html":"Metalations <span class=\"etd-inline-math\">&alpha;\\sp\\prime</span> and <span class=\"etd-inline-math\">&beta;</span> to a tertiary amide have been investigated. Control and understanding of the regiochemistry of these novel metalations is discussed.","abstract_has_math":true,"creators":["Wallin, Anne Parson"],"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":2014,"date_issued":"2014-12-17T21:29:00Z","date_published":"2014-12-17T21:29:00Z","updated_at":"2026-07-22T22:26:06Z","subjects":["Chemistry, Organic"],"languages":[],"rights":[],"rights_urls":[],"identifier_entries":[{"key":"dc:identifier","label":"Identifier","values":["(UMI)AAI8908884"],"render_values":[{"text":"(UMI)AAI8908884","href":null,"code":true}]}]},"links":{"outbound_url":"http://hdl.handle.net/2142/72266","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":["Wallin, Anne Parson"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2014-12-17T21:29:00Z","10000-01-01","1988"]},{"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/2142/72266","(UMI)AAI8908884"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Metalations $\\alpha\\sp\\prime$ and $\\beta$ to a tertiary amide have been investigated. Control and understanding of the regiochemistry of these novel metalations is discussed.","In the $\\alpha\\sp\\prime$ lithiation of a tertiary amide, the use of allyl or benzyl anion stabilizing groups allows for $\\alpha\\sp\\prime$ deprotonation anti to the amide carbonyl as shown for the reactions of syn-N-n-pro-pyl, anti-N-(2-propenyl)-2,4,6-triisopropylbenzamide and syn-N-isopropyl,anti-N-benzyl-2,4,6-triisopropylbenzamide with $s$-butyl-lithium/tetramethylethylenediamine. The rates of isomerization about the amide bond for several N,N-dialkyl-2,4,6-triisopropylbenzamides have been determined, and the investigation of both rotational isomers in these metalation/substitution sequences provides the first unambiguous evidence of a lithiation anti to a directing group for a dipole stabilization carbanion.","It has been shown that the amide provides at least a three-fold enhancement in the acidity of an $\\alpha\\sp\\prime$ amido anion over that of an $\\alpha$ amino anion. The effect of amide structure, base and solvent on a number of related $\\alpha\\sp\\prime$ lithiations has been studied.","In the $\\beta$ lithiations of selected tertiary amides we have found the preferential deprotonation of a $\\beta$ hydrogen over a more acidic $\\alpha$ proton can be observed. Specifically both the $R\\sp\\*,R\\sp\\*$ and $R\\sp\\*,S\\sp\\*$ diastereomers of N,N-diisopropyl-2,3-dimethyl-4-pentene-carboxamides and of N,N-diisopropyl-2-methyl-3-phenylthiobutanecarboxamides upon treatment with $s$-butyllithium/tetramethylethylenediamine and trapping with methanol-d1 give deuteriation at the $\\beta$ position. The $(R\\sp\\*,R\\sp\\*)N,N$-diisopropyl-2-methyl-3-phenylbutanecarboxamide also undergoes $\\beta$ deprotonation, but $\\alpha$ deprotonation is observed for $(R\\sp\\*,S\\sp\\*)N,N$-diisopropyl-2-methyl-3-phenylbutanecarboxamide. The $\\beta$ lithiation is under kinetic control but gives an equilibrated $\\beta$ lithio amide which then reacts with an electrophile under kinetic control. A model which rationalizes the kinetic competition between $\\beta$ and $\\alpha$ lithiation is presented.","Made available in DSpace on 2014-12-17T21:29:00Z (GMT). No. of bitstreams: 1 8908884.pdf: 8153973 bytes, checksum: 1230710f8fe27d505a0a298e1424708f (MD5) Previous issue date: 1988","Embargo set by: Seth Robbins for item 72434 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","194 p.","Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1988."]},{"key":"dc:title","label":"Title","values":["Direction and Stabilization of Alpha' and Beta Metalations by Tertiary Carboxamides"]}]}],"canonical_facts":{"dc:contributor":["Beak, Peter"],"dc:creator":["Wallin, Anne Parson"],"dc:date":["2014-12-17T21:29:00Z","10000-01-01","1988"],"dc:description":["Metalations $\\alpha\\sp\\prime$ and $\\beta$ to a tertiary amide have been investigated. Control and understanding of the regiochemistry of these novel metalations is discussed.","In the $\\alpha\\sp\\prime$ lithiation of a tertiary amide, the use of allyl or benzyl anion stabilizing groups allows for $\\alpha\\sp\\prime$ deprotonation anti to the amide carbonyl as shown for the reactions of syn-N-n-pro-pyl, anti-N-(2-propenyl)-2,4,6-triisopropylbenzamide and syn-N-isopropyl,anti-N-benzyl-2,4,6-triisopropylbenzamide with $s$-butyl-lithium/tetramethylethylenediamine. The rates of isomerization about the amide bond for several N,N-dialkyl-2,4,6-triisopropylbenzamides have been determined, and the investigation of both rotational isomers in these metalation/substitution sequences provides the first unambiguous evidence of a lithiation anti to a directing group for a dipole stabilization carbanion.","It has been shown that the amide provides at least a three-fold enhancement in the acidity of an $\\alpha\\sp\\prime$ amido anion over that of an $\\alpha$ amino anion. The effect of amide structure, base and solvent on a number of related $\\alpha\\sp\\prime$ lithiations has been studied.","In the $\\beta$ lithiations of selected tertiary amides we have found the preferential deprotonation of a $\\beta$ hydrogen over a more acidic $\\alpha$ proton can be observed. Specifically both the $R\\sp\\*,R\\sp\\*$ and $R\\sp\\*,S\\sp\\*$ diastereomers of N,N-diisopropyl-2,3-dimethyl-4-pentene-carboxamides and of N,N-diisopropyl-2-methyl-3-phenylthiobutanecarboxamides upon treatment with $s$-butyllithium/tetramethylethylenediamine and trapping with methanol-d1 give deuteriation at the $\\beta$ position. The $(R\\sp\\*,R\\sp\\*)N,N$-diisopropyl-2-methyl-3-phenylbutanecarboxamide also undergoes $\\beta$ deprotonation, but $\\alpha$ deprotonation is observed for $(R\\sp\\*,S\\sp\\*)N,N$-diisopropyl-2-methyl-3-phenylbutanecarboxamide. The $\\beta$ lithiation is under kinetic control but gives an equilibrated $\\beta$ lithio amide which then reacts with an electrophile under kinetic control. A model which rationalizes the kinetic competition between $\\beta$ and $\\alpha$ lithiation is presented.","Made available in DSpace on 2014-12-17T21:29:00Z (GMT). No. of bitstreams: 1 8908884.pdf: 8153973 bytes, checksum: 1230710f8fe27d505a0a298e1424708f (MD5) Previous issue date: 1988","Embargo set by: Seth Robbins for item 72434 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","194 p.","Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1988."],"dc:identifier":["http://hdl.handle.net/2142/72266","(UMI)AAI8908884"],"dc:subject":["Chemistry, Organic"],"dc:title":["Direction and Stabilization of Alpha' and Beta Metalations by Tertiary Carboxamides"],"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":"2026-07-22T22:26:06Z"}