{"id":{"repo_id":"uiuc","oai_identifier":"oai:www.ideals.illinois.edu:2142/67281"},"canonical_url":"https://search.dev.ndltd.org/etd/uiuc/oai:www.ideals.illinois.edu:2142/67281","repository":{"repo_id":"uiuc","name":"University of Illinois - Urbana-Champaign","base_url":"https://www.ideals.illinois.edu/oai-pmh"},"display":{"title":"The Total Synthesis of (-)-Prezizaene, (-)-Prezizanol, and Other Perzizanoid Sesquiterpenes","abstract":"The synthesis of four related sesquiterpenes was accomplished by elaboration of the chiral precursor pulegone. The ring system of (-)-prezizaene and (-)-prezizonal was constructed by intramolecular ring expansion of a diazo ethyl hydrindanone. (-)-Georgeone and (-)-georgeol containing a C-6 methyl group were formed by pinacolic rearrangement of a 3a,6-ethanoindene-diol. Favorskii rearrangement of (+)-pulegone and ozonolysis furnished ethyl 5-methyl-2-oxo-cyclopentane carboxylate which was annelated with methyl vinyl ketone to give a mixture of diastereomeric hydrindenones. Hydrogenation to ethyl 3-methyl-6-oxo-cis-hexahydroindane-3a-carboxylate was stereospecific. Ketone protection, reduction of the ester and sulphonylation gave 7a-hydroxymethyl-1-methyl-cis-hexahydroindane-5-one ethylene ketal as a single isomer after crystallization. An X-ray structure determination confirmed the all cis stereochemistry at the three chiral centers. Reduction and hydrolysis afforded a dimethyl ketone which was identical with a sample prepared independently.","abstract_html":"The synthesis of four related sesquiterpenes was accomplished by elaboration of the chiral precursor pulegone. The ring system of (-)-prezizaene and (-)-prezizonal was constructed by intramolecular ring expansion of a diazo ethyl hydrindanone. (-)-Georgeone and (-)-georgeol containing a C-6 methyl group were formed by pinacolic rearrangement of a 3a,6-ethanoindene-diol. Favorskii rearrangement of (+)-pulegone and ozonolysis furnished ethyl 5-methyl-2-oxo-cyclopentane carboxylate which was annelated with methyl vinyl ketone to give a mixture of diastereomeric hydrindenones. Hydrogenation to ethyl 3-methyl-6-oxo-cis-hexahydroindane-3a-carboxylate was stereospecific. Ketone protection, reduction of the ester and sulphonylation gave 7a-hydroxymethyl-1-methyl-cis-hexahydroindane-5-one ethylene ketal as a single isomer after crystallization. An X-ray structure determination confirmed the all cis stereochemistry at the three chiral centers. Reduction and hydrolysis afforded a dimethyl ketone which was identical with a sample prepared independently.","abstract_has_math":false,"creators":["Roach, Paula Marianne"],"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":"2014-12-13T20:11:20Z","date_published":"2014-12-13T20:11:20Z","updated_at":"2026-07-22T22:25:57Z","subjects":["Chemistry, Organic"],"languages":["eng"],"rights":[],"rights_urls":[],"identifier_entries":[{"key":"dc:identifier","label":"Identifier","values":["(UMI)AAI8127678"],"render_values":[{"text":"(UMI)AAI8127678","href":null,"code":true}]}]},"links":{"outbound_url":"http://hdl.handle.net/2142/67281","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:creator","label":"Author","values":["Roach, Paula Marianne"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2014-12-13T20:11:20Z","10000-01-01","1981"]},{"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"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["http://hdl.handle.net/2142/67281","(UMI)AAI8127678"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["The synthesis of four related sesquiterpenes was accomplished by elaboration of the chiral precursor pulegone. The ring system of (-)-prezizaene and (-)-prezizonal was constructed by intramolecular ring expansion of a diazo ethyl hydrindanone. (-)-Georgeone and (-)-georgeol containing a C-6 methyl group were formed by pinacolic rearrangement of a 3a,6-ethanoindene-diol. Favorskii rearrangement of (+)-pulegone and ozonolysis furnished ethyl 5-methyl-2-oxo-cyclopentane carboxylate which was annelated with methyl vinyl ketone to give a mixture of diastereomeric hydrindenones. Hydrogenation to ethyl 3-methyl-6-oxo-cis-hexahydroindane-3a-carboxylate was stereospecific. Ketone protection, reduction of the ester and sulphonylation gave 7a-hydroxymethyl-1-methyl-cis-hexahydroindane-5-one ethylene ketal as a single isomer after crystallization. An X-ray structure determination confirmed the all cis stereochemistry at the three chiral centers. Reduction and hydrolysis afforded a dimethyl ketone which was identical with a sample prepared independently.","Cyanide displacement under solid-liquid phase transfer conditions and reduction of the resulting nitrile provided a ketal amine. Benzoylation, hydrolysis, and nitrosation gave an N-nitroso amide. Treatment with potassium t-butoxide in t-amyl alcohol formed the diazo group which, after intramolecular addition to the ketone and rearrangement, afforded a ca. 1:1 mixture of two tricyclic ketones. These were identified as a 3-methyl-2,3,5,6,8,8a-hexahydro-1H-3a,6-methanoazulene-7(4H)-one and 3-methyl-octahydro-6H-3a,7-methanoazulene-6-one by selenation of the latter and oxidation and elimination to an (alpha),(beta)-unsaturated ketone. Alkylation, methyl lithium addition, and dehydration gave (-)-prezizanol and (-)-prezizaene which were completely identical with the natural products.","Oxidation of the ketal amine followed by hydrolysis afforded a nitro ketone which underwent aldol condensation to a tricyclic nitro alcohol containing the 3a,6-ethanohydrindane skeleton. Ozonolysis of the nitronate salt to 6-hydroxy-3-methyl-octahydro-3a,6-ethano-3aH-inden-5-one and methyl lithium addition provided a mixture of diasteromeric diols which under acidic conditions, underwent pinacolic rearrangement to a single 3a,6-methanoperhydroazulene-7-one. Methylation gave (-)-georgeone (3,6,8,8-tetramethyl-2,3,5,6,8,8a-hexahydro-1H-3a,6-methanoazulene-7(4H)-one, and hydride reduction furnished (-)-georgeol. The spectral properities of both compounds were comparable to those of the natural products.","Made available in DSpace on 2014-12-13T20:11:20Z (GMT). No. of bitstreams: 1 8127678.pdf: 5452357 bytes, checksum: 7eaa918d17e33d55e4f17d57b4e534d3 (MD5) Previous issue date: 1981","Embargo set by: Seth Robbins for item 67459 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","190 p.","Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1981."]},{"key":"dc:title","label":"Title","values":["The Total Synthesis of (-)-Prezizaene, (-)-Prezizanol, and Other Perzizanoid Sesquiterpenes"]}]}],"canonical_facts":{"dc:creator":["Roach, Paula Marianne"],"dc:date":["2014-12-13T20:11:20Z","10000-01-01","1981"],"dc:description":["The synthesis of four related sesquiterpenes was accomplished by elaboration of the chiral precursor pulegone. The ring system of (-)-prezizaene and (-)-prezizonal was constructed by intramolecular ring expansion of a diazo ethyl hydrindanone. (-)-Georgeone and (-)-georgeol containing a C-6 methyl group were formed by pinacolic rearrangement of a 3a,6-ethanoindene-diol. Favorskii rearrangement of (+)-pulegone and ozonolysis furnished ethyl 5-methyl-2-oxo-cyclopentane carboxylate which was annelated with methyl vinyl ketone to give a mixture of diastereomeric hydrindenones. Hydrogenation to ethyl 3-methyl-6-oxo-cis-hexahydroindane-3a-carboxylate was stereospecific. Ketone protection, reduction of the ester and sulphonylation gave 7a-hydroxymethyl-1-methyl-cis-hexahydroindane-5-one ethylene ketal as a single isomer after crystallization. An X-ray structure determination confirmed the all cis stereochemistry at the three chiral centers. Reduction and hydrolysis afforded a dimethyl ketone which was identical with a sample prepared independently.","Cyanide displacement under solid-liquid phase transfer conditions and reduction of the resulting nitrile provided a ketal amine. Benzoylation, hydrolysis, and nitrosation gave an N-nitroso amide. Treatment with potassium t-butoxide in t-amyl alcohol formed the diazo group which, after intramolecular addition to the ketone and rearrangement, afforded a ca. 1:1 mixture of two tricyclic ketones. These were identified as a 3-methyl-2,3,5,6,8,8a-hexahydro-1H-3a,6-methanoazulene-7(4H)-one and 3-methyl-octahydro-6H-3a,7-methanoazulene-6-one by selenation of the latter and oxidation and elimination to an (alpha),(beta)-unsaturated ketone. Alkylation, methyl lithium addition, and dehydration gave (-)-prezizanol and (-)-prezizaene which were completely identical with the natural products.","Oxidation of the ketal amine followed by hydrolysis afforded a nitro ketone which underwent aldol condensation to a tricyclic nitro alcohol containing the 3a,6-ethanohydrindane skeleton. Ozonolysis of the nitronate salt to 6-hydroxy-3-methyl-octahydro-3a,6-ethano-3aH-inden-5-one and methyl lithium addition provided a mixture of diasteromeric diols which under acidic conditions, underwent pinacolic rearrangement to a single 3a,6-methanoperhydroazulene-7-one. Methylation gave (-)-georgeone (3,6,8,8-tetramethyl-2,3,5,6,8,8a-hexahydro-1H-3a,6-methanoazulene-7(4H)-one, and hydride reduction furnished (-)-georgeol. The spectral properities of both compounds were comparable to those of the natural products.","Made available in DSpace on 2014-12-13T20:11:20Z (GMT). No. of bitstreams: 1 8127678.pdf: 5452357 bytes, checksum: 7eaa918d17e33d55e4f17d57b4e534d3 (MD5) Previous issue date: 1981","Embargo set by: Seth Robbins for item 67459 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","190 p.","Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1981."],"dc:identifier":["http://hdl.handle.net/2142/67281","(UMI)AAI8127678"],"dc:language":["eng"],"dc:subject":["Chemistry, Organic"],"dc:title":["The Total Synthesis of (-)-Prezizaene, (-)-Prezizanol, and Other Perzizanoid Sesquiterpenes"],"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":"2026-07-22T22:25:57Z"}