{"id":{"repo_id":"uiuc","oai_identifier":"oai:www.ideals.illinois.edu:2142/19631"},"canonical_url":"https://search.dev.ndltd.org/etd/uiuc/oai:www.ideals.illinois.edu:2142/19631","repository":{"repo_id":"uiuc","name":"University of Illinois - Urbana-Champaign","base_url":"https://www.ideals.illinois.edu/oai-pmh"},"display":{"title":"Part I. Development of an enantioselective cyclopropanation reagent. Part II. Studies on the addition of organometallic reagents to imine derivatives","abstract":"Efforts to develop an enantioselective zinc-based cyclopropanation reagent are described. Enantioselectivities of up to 24% e.e. were achieved using N-methylephedrine as a chiral controller ligand for iodomethylzinc cyclopropanations of cinnamyl alcohol. Chiral bis-ether complexes of bis(iodomethyl)zinc were found to react sluggishly and without enantiocontrol, indicating that the use of chelating ligands dramatically attenuates the reactivity of iodomethylzinc species.","abstract_html":"Efforts to develop an enantioselective zinc-based cyclopropanation reagent are described. Enantioselectivities of up to 24% e.e. were achieved using N-methylephedrine as a chiral controller ligand for iodomethylzinc cyclopropanations of cinnamyl alcohol. Chiral bis-ether complexes of bis(iodomethyl)zinc were found to react sluggishly and without enantiocontrol, indicating that the use of chelating ligands dramatically attenuates the reactivity of iodomethylzinc species.","abstract_has_math":false,"creators":["Edwards, James Patrick"],"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":"2011-05-07T12:13:36Z","date_published":"2011-05-07T12:13:36Z","updated_at":"2026-07-22T22:25:14Z","subjects":["Chemistry, Organic"],"languages":["eng"],"rights":["Copyright 1991 Edwards, James Patrick"],"rights_urls":[],"identifier_entries":[{"key":"dc:identifier","label":"Identifier","values":["AAI9210792","(UMI)AAI9210792"],"render_values":[{"text":"AAI9210792","href":null,"code":true},{"text":"(UMI)AAI9210792","href":null,"code":true}]}]},"links":{"outbound_url":"http://hdl.handle.net/2142/19631","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":["Edwards, James Patrick"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2011-05-07T12:13:36Z","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 Edwards, James Patrick"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["AAI9210792","(UMI)AAI9210792","http://hdl.handle.net/2142/19631"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Efforts to develop an enantioselective zinc-based cyclopropanation reagent are described. Enantioselectivities of up to 24% e.e. were achieved using N-methylephedrine as a chiral controller ligand for iodomethylzinc cyclopropanations of cinnamyl alcohol. Chiral bis-ether complexes of bis(iodomethyl)zinc were found to react sluggishly and without enantiocontrol, indicating that the use of chelating ligands dramatically attenuates the reactivity of iodomethylzinc species.","Extensive spectroscopic studies of halomethylzinc reagents are also reported. NMR spectroscopic studies demonstrated for the first time the formation of bis(iodomethyl)zinc and bis(chloromethyl)zinc from the reaction of diethylzinc with diiodomethane and chloroiodo-methane respectively. The conversion of bis(iodomethyl)zinc complexes to iodomethylzinc iodide complexes was also demonstrated. These latter species were determined to exist predominantly as bis(iodomethyl)zinc/zinc iodide species in acetone solution. The first X-ray crystallographic analysis of an iodomethylzinc compound is also described in detail.","A study of the addition of organocerium reagents to imine derivatives is also reported. The ratio of alkyllithium reagent to cerium(III) chloride used to generate the organocerium reagent was shown to have a dramatic effect on the yield of additions to N,N-dimethylhydrazones. Ratios of greater than 3:1 resulted in much lower yields using methyllithium as the limiting reagent, while lowering the ratio resulted in a small but measurable improvement in yield. Organocerium additions to chiral 2-substituted pyrrolidine hydrazones were also studied, and were shown to proceed with high levels of diastereocontrol without the need of coordinating appendages in the auxiliary side-chain, indicating that the diastereocontrol observed in additions to SAMP-hydrazones is not the result of chelation-control.","Made available in DSpace on 2011-05-07T12:13:36Z (GMT). No. of bitstreams: 2 license.txt: 4922 bytes, checksum: 910b249b4beec47e7ab768910c8f966f (MD5) 9210792.pdf: 15070927 bytes, checksum: 9e82832fd5d76daad04aa87142cf35da (MD5) Previous issue date: 1991","Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Howard Ding (hding2@illinois.edu) on 2011-05-07T14:38:21Z Item is restricted indefinitely.","Restriction data tranferred 2014-07-01T11:15:58-05:00 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":["Part I. Development of an enantioselective cyclopropanation reagent. Part II. Studies on the addition of organometallic reagents to imine derivatives"]}]}],"canonical_facts":{"dc:contributor":["Denmark, Scott E."],"dc:creator":["Edwards, James Patrick"],"dc:date":["2011-05-07T12:13:36Z","10000-01-01","1991"],"dc:description":["Efforts to develop an enantioselective zinc-based cyclopropanation reagent are described. Enantioselectivities of up to 24% e.e. were achieved using N-methylephedrine as a chiral controller ligand for iodomethylzinc cyclopropanations of cinnamyl alcohol. Chiral bis-ether complexes of bis(iodomethyl)zinc were found to react sluggishly and without enantiocontrol, indicating that the use of chelating ligands dramatically attenuates the reactivity of iodomethylzinc species.","Extensive spectroscopic studies of halomethylzinc reagents are also reported. NMR spectroscopic studies demonstrated for the first time the formation of bis(iodomethyl)zinc and bis(chloromethyl)zinc from the reaction of diethylzinc with diiodomethane and chloroiodo-methane respectively. The conversion of bis(iodomethyl)zinc complexes to iodomethylzinc iodide complexes was also demonstrated. These latter species were determined to exist predominantly as bis(iodomethyl)zinc/zinc iodide species in acetone solution. The first X-ray crystallographic analysis of an iodomethylzinc compound is also described in detail.","A study of the addition of organocerium reagents to imine derivatives is also reported. The ratio of alkyllithium reagent to cerium(III) chloride used to generate the organocerium reagent was shown to have a dramatic effect on the yield of additions to N,N-dimethylhydrazones. Ratios of greater than 3:1 resulted in much lower yields using methyllithium as the limiting reagent, while lowering the ratio resulted in a small but measurable improvement in yield. Organocerium additions to chiral 2-substituted pyrrolidine hydrazones were also studied, and were shown to proceed with high levels of diastereocontrol without the need of coordinating appendages in the auxiliary side-chain, indicating that the diastereocontrol observed in additions to SAMP-hydrazones is not the result of chelation-control.","Made available in DSpace on 2011-05-07T12:13:36Z (GMT). No. of bitstreams: 2 license.txt: 4922 bytes, checksum: 910b249b4beec47e7ab768910c8f966f (MD5) 9210792.pdf: 15070927 bytes, checksum: 9e82832fd5d76daad04aa87142cf35da (MD5) Previous issue date: 1991","Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Howard Ding (hding2@illinois.edu) on 2011-05-07T14:38:21Z Item is restricted indefinitely.","Restriction data tranferred 2014-07-01T11:15:58-05:00 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":["AAI9210792","(UMI)AAI9210792","http://hdl.handle.net/2142/19631"],"dc:language":["eng"],"dc:rights":["Copyright 1991 Edwards, James Patrick"],"dc:subject":["Chemistry, Organic"],"dc:title":["Part I. Development of an enantioselective cyclopropanation reagent. Part II. Studies on the addition of organometallic reagents to imine derivatives"],"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":"2026-07-22T22:25:14Z"}