A novel ceric ammonium nitrate-mediated oxidative cleavage of hemiacetals generated through the use of the zinc carbenoid-mediated tandem chain extension-aldol reaction was developed. This chemistry has been applied towards the formation of a class of natural products, phaseolinic acids, in two steps from a commercially available beta-keto ester, methyl 4-methoxyacetoacetate.
The tandem chain extension-imine capture reaction has also been developed to provide access to beta-proline derivatives. Two activated imines were studied and provided access to different diastereomers, making the chemistry versatile. beta-Keto esters, beta-keto amides, and beta-keto imides were subjected to the tandem chain extension-imine capture reaction conditions and proved to be reasonably successful in most cases. beta-Keto esters were efficient in the synthesis of free --NH beta-proline derivatives in three steps and beta-keto imides were efficient in the synthesis of Boc-protected beta-proline derivatives in just two steps.
The zinc carbenoid-mediated chain extension imine capture reaction has developed into a flexible route in obtaining different diastereomers of protected and unprotected beta-proline derivatives in minimal steps from commercially available starting materials.
","abstract_html":"<p>A novel ceric ammonium nitrate-mediated oxidative cleavage of hemiacetals generated through the use of the zinc carbenoid-mediated tandem chain extension-aldol reaction was developed. This chemistry has been applied towards the formation of a class of natural products, phaseolinic acids, in two steps from a commercially available beta-keto ester, methyl 4-methoxyacetoacetate.</p><p>The tandem chain extension-imine capture reaction has also been developed to provide access to beta-proline derivatives. Two activated imines were studied and provided access to different diastereomers, making the chemistry versatile. beta-Keto esters, beta-keto amides, and beta-keto imides were subjected to the tandem chain extension-imine capture reaction conditions and proved to be reasonably successful in most cases. beta-Keto esters were efficient in the synthesis of free --NH beta-proline derivatives in three steps and beta-keto imides were efficient in the synthesis of Boc-protected beta-proline derivatives in just two steps.</p><p>The zinc carbenoid-mediated chain extension imine capture reaction has developed into a flexible route in obtaining different diastereomers of protected and unprotected beta-proline derivatives in minimal steps from commercially available starting materials.</p>","abstract_has_math":false,"creators":["Jacobine, Alexander M"],"institution":null,"degree_name":"Doctor of Philosophy","degree_level":"Dissertation","degree_discipline":null,"degree_department":null,"school":null,"contributors":["Charles K Zercher"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2010,"date_issued":"2010-01-01T08:00:00Z","date_published":"2010-01-01T08:00:00Z","updated_at":"2026-07-24T05:22:31Z","subjects":["Chemistry","Organic"],"languages":[],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"https://scholars.unh.edu/dissertation/523","outbound_label":"Repository record","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Charles K Zercher"]},{"key":"dc:creator","label":"Author","values":["Jacobine, Alexander M"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"thesis:degree_level","label":"Degree Level","values":["Dissertation"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Doctor of Philosophy"]}]},{"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":["https://scholars.unh.edu/dissertation/523"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["A novel ceric ammonium nitrate-mediated oxidative cleavage of hemiacetals generated through the use of the zinc carbenoid-mediated tandem chain extension-aldol reaction was developed. This chemistry has been applied towards the formation of a class of natural products, phaseolinic acids, in two steps from a commercially available beta-keto ester, methyl 4-methoxyacetoacetate.
The tandem chain extension-imine capture reaction has also been developed to provide access to beta-proline derivatives. Two activated imines were studied and provided access to different diastereomers, making the chemistry versatile. beta-Keto esters, beta-keto amides, and beta-keto imides were subjected to the tandem chain extension-imine capture reaction conditions and proved to be reasonably successful in most cases. beta-Keto esters were efficient in the synthesis of free --NH beta-proline derivatives in three steps and beta-keto imides were efficient in the synthesis of Boc-protected beta-proline derivatives in just two steps.
The zinc carbenoid-mediated chain extension imine capture reaction has developed into a flexible route in obtaining different diastereomers of protected and unprotected beta-proline derivatives in minimal steps from commercially available starting materials.
"]},{"key":"dc:title","label":"Title","values":["I Ceric ammonium nitrate-mediated oxidative cleavages of hemiacetals II Synthesis of beta-proline derivatives through the tandem chain extension-imine capture reaction"]}]}],"canonical_facts":{"dc:contributor":["Charles K Zercher"],"dc:creator":["Jacobine, Alexander M"],"dc:description.abstract":["A novel ceric ammonium nitrate-mediated oxidative cleavage of hemiacetals generated through the use of the zinc carbenoid-mediated tandem chain extension-aldol reaction was developed. This chemistry has been applied towards the formation of a class of natural products, phaseolinic acids, in two steps from a commercially available beta-keto ester, methyl 4-methoxyacetoacetate.
The tandem chain extension-imine capture reaction has also been developed to provide access to beta-proline derivatives. Two activated imines were studied and provided access to different diastereomers, making the chemistry versatile. beta-Keto esters, beta-keto amides, and beta-keto imides were subjected to the tandem chain extension-imine capture reaction conditions and proved to be reasonably successful in most cases. beta-Keto esters were efficient in the synthesis of free --NH beta-proline derivatives in three steps and beta-keto imides were efficient in the synthesis of Boc-protected beta-proline derivatives in just two steps.
The zinc carbenoid-mediated chain extension imine capture reaction has developed into a flexible route in obtaining different diastereomers of protected and unprotected beta-proline derivatives in minimal steps from commercially available starting materials.
"],"dc:identifier":["https://scholars.unh.edu/dissertation/523"],"dc:subject":["Chemistry","Organic"],"dc:title":["I Ceric ammonium nitrate-mediated oxidative cleavages of hemiacetals II Synthesis of beta-proline derivatives through the tandem chain extension-imine capture reaction"],"thesis:degree_level":["Dissertation"],"thesis:degree_name":["Doctor of Philosophy"]},"updated_at":"2026-07-24T05:22:31Z"}