{"id":{"repo_id":"catania","oai_identifier":"oai:www.iris.unict.it:20.500.11769/587044"},"canonical_url":"https://search.dev.ndltd.org/etd/catania/oai:www.iris.unict.it:20.500.11769/587044","repository":{"repo_id":"catania","name":"Università degli Studi di Catania","base_url":"https://www.iris.unict.it/oai/request"},"display":{"title":"Studies on extensions of tert-amino effect: Ring-fusion to bridged biaryls and steroids","abstract":"Studies on extensions of tert-amino effect: Ring-fusion to bridged biaryls and steroids The term t (later tert)-amino effect was introduced by Meth-Cohn and Suschitzky to generalize the thermal isomerization of ortho-substituted tertiary anilines to benzo-fused heterocyclic systems. In type 2 reactions, an ortho-vinyl tert-aniline gives a tetrahydroquinoline via C-C bond formation between the beta-vinyl carbon and the alfa-methylene carbon of the amino group; the reaction could be extended to heterocyclic and bi- and tri-aryl analogues of anilines to obtain novel medium or larger ring systems. It has recently received much attention due to its wide scope and predictable regio- and stereoselectivity. In the present work we report on our efforts to extend the type 2 tert-amino effect to non-conjugated systems, including: I) biaryls connected with a saturated chain bearing the vinyl and the amino moieties in ortho-ortho position in the aromatic rings; II) steroids possessing vinyl and amino substituents in the D-ring Concerning the biaryl compounds, a methylamino-N-methyl or a CH2-O chains were used. In the first case (methylamino-N-methyl chain), the presence of two amino groups positioned ortho to a vinyl substituent in the same molecule, a priori, could lead to three different hydrogen migrations and, accordingly, different types of cyclizations. Although, isomerizations with the involvement of N-methyl group with a preference over the involvement of an N-benzyl might not be expected to take place at all, possible formations of six- and/or ten-membered rings (with N-benzyl carbons) could be considered. Not surprisingly, our isomerization experiment led to a six-membered ring. In case of the CH2-O chain, although, according to DSC, a possible ring closure reaction might have taken place in temperature range of 158-191.11 °C, the corresponding cyclized product, could not be found in our preparative experiments Next, as a fully unexplored field of tert-amino effect, steroids were investigated. We prepared steroids properly functionalized in D-ring to study type 2 tert-amino effect in a non-aromatic system and utilize the isomerization reaction to open a new way to D-fused steroid-ring systems. Cyclization of these steroids did indeed occurred at high temperature to give two diastereomers in a ca. 1:1 ratio.","abstract_html":"Studies on extensions of tert-amino effect: Ring-fusion to bridged biaryls and steroids The term t (later tert)-amino effect was introduced by Meth-Cohn and Suschitzky to generalize the thermal isomerization of ortho-substituted tertiary anilines to benzo-fused heterocyclic systems. In type 2 reactions, an ortho-vinyl tert-aniline gives a tetrahydroquinoline via C-C bond formation between the beta-vinyl carbon and the alfa-methylene carbon of the amino group; the reaction could be extended to heterocyclic and bi- and tri-aryl analogues of anilines to obtain novel medium or larger ring systems. It has recently received much attention due to its wide scope and predictable regio- and stereoselectivity. In the present work we report on our efforts to extend the type 2 tert-amino effect to non-conjugated systems, including: I) biaryls connected with a saturated chain bearing the vinyl and the amino moieties in ortho-ortho position in the aromatic rings; II) steroids possessing vinyl and amino substituents in the D-ring Concerning the biaryl compounds, a methylamino-N-methyl or a CH2-O chains were used. In the first case (methylamino-N-methyl chain), the presence of two amino groups positioned ortho to a vinyl substituent in the same molecule, a priori, could lead to three different hydrogen migrations and, accordingly, different types of cyclizations. Although, isomerizations with the involvement of N-methyl group with a preference over the involvement of an N-benzyl might not be expected to take place at all, possible formations of six- and/or ten-membered rings (with N-benzyl carbons) could be considered. Not surprisingly, our isomerization experiment led to a six-membered ring. In case of the CH2-O chain, although, according to DSC, a possible ring closure reaction might have taken place in temperature range of 158-191.11 °C, the corresponding cyclized product, could not be found in our preparative experiments Next, as a fully unexplored field of tert-amino effect, steroids were investigated. We prepared steroids properly functionalized in D-ring to study type 2 tert-amino effect in a non-aromatic system and utilize the isomerization reaction to open a new way to D-fused steroid-ring systems. Cyclization of these steroids did indeed occurred at high temperature to give two diastereomers in a ca. 1:1 ratio.","abstract_has_math":false,"creators":["BOTTINO, PAOLA"],"institution":"Università degli studi di Catania","degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":null,"school":null,"contributors":["RONSISVALLE, Giuseppe"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2012,"date_issued":"2012-12-09","date_published":"2012-12-09","updated_at":"2026-07-24T01:35:22Z","subjects":["Tert-amino effect, steroids, push-pull ethylenes"],"languages":["eng"],"rights":["info:eu-repo/semantics/openAccess","license:PUBBLICO - Pubblico con Copyright","license uri:iris.PUB02"],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"https://hdl.handle.net/20.500.11769/587044","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Bottino, Paola","RONSISVALLE, Giuseppe"]},{"key":"dc:creator","label":"Author","values":["BOTTINO, PAOLA"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2012-12-09"]},{"key":"dc:publisher","label":"Institution","values":["Università degli studi di Catania","place:Catania"]},{"key":"dc:type","label":"Dc Type","values":["info:eu-repo/semantics/doctoralThesis"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Tert-amino effect, steroids, push-pull ethylenes"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["eng"]},{"key":"dc:rights","label":"Dc Rights","values":["info:eu-repo/semantics/openAccess","license:PUBBLICO - Pubblico con Copyright","license uri:iris.PUB02"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["https://hdl.handle.net/20.500.11769/587044"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Studies on extensions of tert-amino effect: Ring-fusion to bridged biaryls and steroids The term t (later tert)-amino effect was introduced by Meth-Cohn and Suschitzky to generalize the thermal isomerization of ortho-substituted tertiary anilines to benzo-fused heterocyclic systems. In type 2 reactions, an ortho-vinyl tert-aniline gives a tetrahydroquinoline via C-C bond formation between the beta-vinyl carbon and the alfa-methylene carbon of the amino group; the reaction could be extended to heterocyclic and bi- and tri-aryl analogues of anilines to obtain novel medium or larger ring systems. It has recently received much attention due to its wide scope and predictable regio- and stereoselectivity. In the present work we report on our efforts to extend the type 2 tert-amino effect to non-conjugated systems, including: I) biaryls connected with a saturated chain bearing the vinyl and the amino moieties in ortho-ortho position in the aromatic rings; II) steroids possessing vinyl and amino substituents in the D-ring Concerning the biaryl compounds, a methylamino-N-methyl or a CH2-O chains were used. In the first case (methylamino-N-methyl chain), the presence of two amino groups positioned ortho to a vinyl substituent in the same molecule, a priori, could lead to three different hydrogen migrations and, accordingly, different types of cyclizations. Although, isomerizations with the involvement of N-methyl group with a preference over the involvement of an N-benzyl might not be expected to take place at all, possible formations of six- and/or ten-membered rings (with N-benzyl carbons) could be considered. Not surprisingly, our isomerization experiment led to a six-membered ring. In case of the CH2-O chain, although, according to DSC, a possible ring closure reaction might have taken place in temperature range of 158-191.11 °C, the corresponding cyclized product, could not be found in our preparative experiments Next, as a fully unexplored field of tert-amino effect, steroids were investigated. We prepared steroids properly functionalized in D-ring to study type 2 tert-amino effect in a non-aromatic system and utilize the isomerization reaction to open a new way to D-fused steroid-ring systems. Cyclization of these steroids did indeed occurred at high temperature to give two diastereomers in a ca. 1:1 ratio."]},{"key":"dc:title","label":"Title","values":["Studies on extensions of tert-amino effect: Ring-fusion to bridged biaryls and steroids"]}]}],"canonical_facts":{"dc:contributor":["Bottino, Paola","RONSISVALLE, Giuseppe"],"dc:creator":["BOTTINO, PAOLA"],"dc:date":["2012-12-09"],"dc:description":["Studies on extensions of tert-amino effect: Ring-fusion to bridged biaryls and steroids The term t (later tert)-amino effect was introduced by Meth-Cohn and Suschitzky to generalize the thermal isomerization of ortho-substituted tertiary anilines to benzo-fused heterocyclic systems. In type 2 reactions, an ortho-vinyl tert-aniline gives a tetrahydroquinoline via C-C bond formation between the beta-vinyl carbon and the alfa-methylene carbon of the amino group; the reaction could be extended to heterocyclic and bi- and tri-aryl analogues of anilines to obtain novel medium or larger ring systems. It has recently received much attention due to its wide scope and predictable regio- and stereoselectivity. In the present work we report on our efforts to extend the type 2 tert-amino effect to non-conjugated systems, including: I) biaryls connected with a saturated chain bearing the vinyl and the amino moieties in ortho-ortho position in the aromatic rings; II) steroids possessing vinyl and amino substituents in the D-ring Concerning the biaryl compounds, a methylamino-N-methyl or a CH2-O chains were used. In the first case (methylamino-N-methyl chain), the presence of two amino groups positioned ortho to a vinyl substituent in the same molecule, a priori, could lead to three different hydrogen migrations and, accordingly, different types of cyclizations. Although, isomerizations with the involvement of N-methyl group with a preference over the involvement of an N-benzyl might not be expected to take place at all, possible formations of six- and/or ten-membered rings (with N-benzyl carbons) could be considered. Not surprisingly, our isomerization experiment led to a six-membered ring. In case of the CH2-O chain, although, according to DSC, a possible ring closure reaction might have taken place in temperature range of 158-191.11 °C, the corresponding cyclized product, could not be found in our preparative experiments Next, as a fully unexplored field of tert-amino effect, steroids were investigated. We prepared steroids properly functionalized in D-ring to study type 2 tert-amino effect in a non-aromatic system and utilize the isomerization reaction to open a new way to D-fused steroid-ring systems. Cyclization of these steroids did indeed occurred at high temperature to give two diastereomers in a ca. 1:1 ratio."],"dc:identifier":["https://hdl.handle.net/20.500.11769/587044"],"dc:language":["eng"],"dc:publisher":["Università degli studi di Catania","place:Catania"],"dc:rights":["info:eu-repo/semantics/openAccess","license:PUBBLICO - Pubblico con Copyright","license uri:iris.PUB02"],"dc:subject":["Tert-amino effect, steroids, push-pull ethylenes"],"dc:title":["Studies on extensions of tert-amino effect: Ring-fusion to bridged biaryls and steroids"],"dc:type":["info:eu-repo/semantics/doctoralThesis"]},"updated_at":"2026-07-24T01:35:22Z"}