{"id":{"repo_id":"uiuc","oai_identifier":"oai:www.ideals.illinois.edu:2142/20131"},"canonical_url":"https://search.dev.ndltd.org/etd/uiuc/oai:www.ideals.illinois.edu:2142/20131","repository":{"repo_id":"uiuc","name":"University of Illinois - Urbana-Champaign","base_url":"https://www.ideals.illinois.edu/oai-pmh"},"display":{"title":"Applications of nitroalkene (4+2); cycloaddition chemistry. The asymmetric synthesis of substituted pyrrolidines and the total synthesis of mesembrine","abstract":"A general route for the preparation of 2,2-disubstituted 1-nitroalkenes has been developed. Conjugate 1,4-addition of zinc cuprates (RCu(CN)ZnI) to easily obtained (E)-1-nitroalkenes, followed by trapping with phenylselenenyl bromide, and subsequent oxidative elimination afforded the corresponding 2,2-disubstituted 1-nitroalkenes in 76-88% yield as E/Z isomeric mixtures ($\\sim$1.0/1.5, E/Z). 2,2-Disubstituted-1-nitroalkenes were found to undergo Lewis acid-promoted (4+2) cycloadditions with n-butyl vinyl ether to afford cyclic nitronates in 76-90% yield. The resulting nitronates were reduced with hydrogen in the presence of platinum oxide to afford 3,3-disubstituted pyrrolidines which were isolated in 70-83% yield as their N-tosyl derivatives. Similarly, cycloadditions of (E)-2-nitrostyrene with 2-substituted enol ethers provided for the stereoselective synthesis of cis- and trans-3,4-disubstituted pyrrolidines.","abstract_html":"A general route for the preparation of 2,2-disubstituted 1-nitroalkenes has been developed. Conjugate 1,4-addition of zinc cuprates (RCu(CN)ZnI) to easily obtained (E)-1-nitroalkenes, followed by trapping with phenylselenenyl bromide, and subsequent oxidative elimination afforded the corresponding 2,2-disubstituted 1-nitroalkenes in 76-88% yield as E/Z isomeric mixtures ($\\sim$1.0/1.5, E/Z). 2,2-Disubstituted-1-nitroalkenes were found to undergo Lewis acid-promoted (4+2) cycloadditions with n-butyl vinyl ether to afford cyclic nitronates in 76-90% yield. The resulting nitronates were reduced with hydrogen in the presence of platinum oxide to afford 3,3-disubstituted pyrrolidines which were isolated in 70-83% yield as their N-tosyl derivatives. Similarly, cycloadditions of (E)-2-nitrostyrene with 2-substituted enol ethers provided for the stereoselective synthesis of cis- and trans-3,4-disubstituted pyrrolidines.","abstract_has_math":true,"creators":["Marcin, Lawrence R."],"institution":"University of Illinois at Urbana-Champaign","degree_name":"Ph.D.","degree_level":"Dissertation","degree_discipline":"Chemistry","degree_department":null,"school":null,"contributors":["Denmark, Scott E."],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2011,"date_issued":"2011-05-07T12:29:47Z","date_published":"2011-05-07T12:29:47Z","updated_at":"2026-07-22T22:25:15Z","subjects":["Chemistry, Organic"],"languages":["eng"],"rights":["Copyright 1996 Marcin, Lawrence R."],"rights_urls":[],"identifier_entries":[{"key":"dc:identifier","label":"Identifier","values":["9780591199345","AAI9712369","(UMI)AAI9712369"],"render_values":[{"text":"9780591199345","href":null,"code":true},{"text":"AAI9712369","href":null,"code":true},{"text":"(UMI)AAI9712369","href":null,"code":true}]}]},"links":{"outbound_url":"http://hdl.handle.net/2142/20131","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Denmark, Scott E."]},{"key":"dc:creator","label":"Author","values":["Marcin, Lawrence R."]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2011-05-07T12:29:47Z","10000-01-01","1996"]},{"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 1996 Marcin, Lawrence R."]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["9780591199345","AAI9712369","(UMI)AAI9712369","http://hdl.handle.net/2142/20131"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["A general route for the preparation of 2,2-disubstituted 1-nitroalkenes has been developed. Conjugate 1,4-addition of zinc cuprates (RCu(CN)ZnI) to easily obtained (E)-1-nitroalkenes, followed by trapping with phenylselenenyl bromide, and subsequent oxidative elimination afforded the corresponding 2,2-disubstituted 1-nitroalkenes in 76-88% yield as E/Z isomeric mixtures ($\\sim$1.0/1.5, E/Z). 2,2-Disubstituted-1-nitroalkenes were found to undergo Lewis acid-promoted (4+2) cycloadditions with n-butyl vinyl ether to afford cyclic nitronates in 76-90% yield. The resulting nitronates were reduced with hydrogen in the presence of platinum oxide to afford 3,3-disubstituted pyrrolidines which were isolated in 70-83% yield as their N-tosyl derivatives. Similarly, cycloadditions of (E)-2-nitrostyrene with 2-substituted enol ethers provided for the stereoselective synthesis of cis- and trans-3,4-disubstituted pyrrolidines.","(E)-2-Substituted 1-nitroalkenes undergo highly diastereoselective (4+2) cycloadditions with the chiral vinyl ethers derived from (R)-2,2-diphenylcyclopentanol and (1R,2S)-2-phenylcyclohexanol to afford nitronates in high yields. The resulting nitronates were reduced to afford enantiomerically enriched pyrrolidines in good yields. A series of 3-substituted pyrrolidines (71-97% ee) were prepared, as well as (3S,4R)-4-methyl-3-phenyl-N-(p-tolylsulfonyl)pyrrolidine (92% ee) and (3S,4S)-3,4-diphenylpyrrolidine (99% ee).","The total synthesis of ($-$)-mesembrine was accomplished in seven steps and 19% yield from a functionalized 2,2-disubstituted 1-nitroalkene, which was prepared in six steps and 34% yield from ethyl 3-bromopropionate. The quaternary, stereogenic center of the natural product was established in 26/1 selectivity through an asymmetric (4+2) cycloaddition with a chiral vinyl ether derived from (1R,2S)-2-(1-methyl-1-phenylethyl)cyclohexanol.","Made available in DSpace on 2011-05-07T12:29:47Z (GMT). No. of bitstreams: 2 license.txt: 4922 bytes, checksum: 910b249b4beec47e7ab768910c8f966f (MD5) 9712369.pdf: 11202409 bytes, checksum: 4b8c4964b5e3c15876d26e1a7ec7b964 (MD5) Previous issue date: 1996","Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Howard Ding (hding2@illinois.edu) on 2011-05-07T14:41:46Z Item is restricted indefinitely.","Restriction data tranferred 2014-07-01T11:18:07-05:00 Original Data Group with Access UIUC Users [automated] Release Date: none Reason: ETDs are only available to UIUC Users without author permission","ETDs are only available to UIUC Users without author permission","U of I Only"]},{"key":"dc:title","label":"Title","values":["Applications of nitroalkene (4+2); cycloaddition chemistry. The asymmetric synthesis of substituted pyrrolidines and the total synthesis of mesembrine"]}]}],"canonical_facts":{"dc:contributor":["Denmark, Scott E."],"dc:creator":["Marcin, Lawrence R."],"dc:date":["2011-05-07T12:29:47Z","10000-01-01","1996"],"dc:description":["A general route for the preparation of 2,2-disubstituted 1-nitroalkenes has been developed. Conjugate 1,4-addition of zinc cuprates (RCu(CN)ZnI) to easily obtained (E)-1-nitroalkenes, followed by trapping with phenylselenenyl bromide, and subsequent oxidative elimination afforded the corresponding 2,2-disubstituted 1-nitroalkenes in 76-88% yield as E/Z isomeric mixtures ($\\sim$1.0/1.5, E/Z). 2,2-Disubstituted-1-nitroalkenes were found to undergo Lewis acid-promoted (4+2) cycloadditions with n-butyl vinyl ether to afford cyclic nitronates in 76-90% yield. The resulting nitronates were reduced with hydrogen in the presence of platinum oxide to afford 3,3-disubstituted pyrrolidines which were isolated in 70-83% yield as their N-tosyl derivatives. Similarly, cycloadditions of (E)-2-nitrostyrene with 2-substituted enol ethers provided for the stereoselective synthesis of cis- and trans-3,4-disubstituted pyrrolidines.","(E)-2-Substituted 1-nitroalkenes undergo highly diastereoselective (4+2) cycloadditions with the chiral vinyl ethers derived from (R)-2,2-diphenylcyclopentanol and (1R,2S)-2-phenylcyclohexanol to afford nitronates in high yields. The resulting nitronates were reduced to afford enantiomerically enriched pyrrolidines in good yields. A series of 3-substituted pyrrolidines (71-97% ee) were prepared, as well as (3S,4R)-4-methyl-3-phenyl-N-(p-tolylsulfonyl)pyrrolidine (92% ee) and (3S,4S)-3,4-diphenylpyrrolidine (99% ee).","The total synthesis of ($-$)-mesembrine was accomplished in seven steps and 19% yield from a functionalized 2,2-disubstituted 1-nitroalkene, which was prepared in six steps and 34% yield from ethyl 3-bromopropionate. The quaternary, stereogenic center of the natural product was established in 26/1 selectivity through an asymmetric (4+2) cycloaddition with a chiral vinyl ether derived from (1R,2S)-2-(1-methyl-1-phenylethyl)cyclohexanol.","Made available in DSpace on 2011-05-07T12:29:47Z (GMT). No. of bitstreams: 2 license.txt: 4922 bytes, checksum: 910b249b4beec47e7ab768910c8f966f (MD5) 9712369.pdf: 11202409 bytes, checksum: 4b8c4964b5e3c15876d26e1a7ec7b964 (MD5) Previous issue date: 1996","Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Howard Ding (hding2@illinois.edu) on 2011-05-07T14:41:46Z Item is restricted indefinitely.","Restriction data tranferred 2014-07-01T11:18:07-05:00 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":["9780591199345","AAI9712369","(UMI)AAI9712369","http://hdl.handle.net/2142/20131"],"dc:language":["eng"],"dc:rights":["Copyright 1996 Marcin, Lawrence R."],"dc:subject":["Chemistry, Organic"],"dc:title":["Applications of nitroalkene (4+2); cycloaddition chemistry. The asymmetric synthesis of substituted pyrrolidines and the total synthesis of mesembrine"],"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":"2026-07-22T22:25:15Z"}