{"id":{"repo_id":"ghent","oai_identifier":"oai:archive.ugent.be:811200"},"canonical_url":"https://search.dev.ndltd.org/etd/ghent/oai:archive.ugent.be:811200","repository":{"repo_id":"ghent","name":"Ghent University","base_url":"https://biblio.ugent.be/oai"},"display":{"title":"Synthesis and application of chiral dienes and chiral imidates as ligands for transition metal catalysis","abstract":"In this dissertation, two main ligandclasses have been studied: chiral diene ligands and chiral imidate ligands. We developed a novel route to synthesize chiral disubstituted bicyclo[2.2.1]heptadienes (R= i-Bu, c-Hex, Benzyl and allyl) starting from enantiomerically pure bistriflate. The synthesized diene ligands were tested in the rhodium(I)-catalyzed 1,4-addition of phenylboronic acids to cyclic enones (up to 96% ee) and α-acetamido acrylic ester and in the rhodium(I)-catalyzed 1,2-addition of phenylboronic acids to benzaldehydes (up to 48% ee). We introduced chiral imidates as a novel nitrogen-based ligand family. These imidates, with an exocyclic nitrogen, have never before been reported in literature. We showed that these imidate ligands could be obtained readily via a one-step synthesis starting from a central precursor in excellent yields. Moreover, imidate ligands could further be fine-tuned when substituents were put on the aromatic ring of the imidate ligand precursor. The synthesized monodentate and bidentate ligands were tested in several asymmetric test reactions. In the copper(I)-catalyzed asymmetric aziridinations, we obtained usually high yields (up to 90% yield) and moderate enantioselectivity (51% ee) with a bidentate imidate ligand. The asymmetric addition of diethylzinc to benzaldehyde resulted in high yields (up to 87% yield) and good enantioselectivities (up to 76% ee). However, the best result was obtained in the asymmetric allylic alkylation with an imidate with a binaphtylbackbone: a moderate yield (53% yield) with an excellent selectivity (95% ee). Futhermore, we developed successfully hybrid imidate-phosphane ligands as a new type of P,N ligands. These ligands are easily accessible in one step via a condensation of a commercially available aminophosphane and an imidate ligand precursor. The ligands were demonstrated to be highly valuable in palladium-catalyzed allylic substitution reactions. Excellent performance of this catalyst system was observed in the allylic alkylation of 1,3-diphenyl-2-propenyl acetate with various nucleophiles (up to 99% yield and >99% ee). Moreover, the allylic alkylation of linear unhindered and cyclic substrates resulted in good conversions and enantioselectivities. The cyclic imidate ligand precursor could also be used efficiently as a synthetic intermediate for the synthesis of chiral oxazoline alcohol ligands and the synthesis of chiral imidazolidines.","abstract_html":"In this dissertation, two main ligandclasses have been studied: chiral diene ligands and chiral imidate ligands. We developed a novel route to synthesize chiral disubstituted bicyclo[2.2.1]heptadienes (R= i-Bu, c-Hex, Benzyl and allyl) starting from enantiomerically pure bistriflate. The synthesized diene ligands were tested in the rhodium(I)-catalyzed 1,4-addition of phenylboronic acids to cyclic enones (up to 96% ee) and α-acetamido acrylic ester and in the rhodium(I)-catalyzed 1,2-addition of phenylboronic acids to benzaldehydes (up to 48% ee). We introduced chiral imidates as a novel nitrogen-based ligand family. These imidates, with an exocyclic nitrogen, have never before been reported in literature. We showed that these imidate ligands could be obtained readily via a one-step synthesis starting from a central precursor in excellent yields. Moreover, imidate ligands could further be fine-tuned when substituents were put on the aromatic ring of the imidate ligand precursor. The synthesized monodentate and bidentate ligands were tested in several asymmetric test reactions. In the copper(I)-catalyzed asymmetric aziridinations, we obtained usually high yields (up to 90% yield) and moderate enantioselectivity (51% ee) with a bidentate imidate ligand. The asymmetric addition of diethylzinc to benzaldehyde resulted in high yields (up to 87% yield) and good enantioselectivities (up to 76% ee). However, the best result was obtained in the asymmetric allylic alkylation with an imidate with a binaphtylbackbone: a moderate yield (53% yield) with an excellent selectivity (95% ee). Futhermore, we developed successfully hybrid imidate-phosphane ligands as a new type of P,N ligands. These ligands are easily accessible in one step via a condensation of a commercially available aminophosphane and an imidate ligand precursor. The ligands were demonstrated to be highly valuable in palladium-catalyzed allylic substitution reactions. Excellent performance of this catalyst system was observed in the allylic alkylation of 1,3-diphenyl-2-propenyl acetate with various nucleophiles (up to 99% yield and >99% ee). Moreover, the allylic alkylation of linear unhindered and cyclic substrates resulted in good conversions and enantioselectivities. The cyclic imidate ligand precursor could also be used efficiently as a synthetic intermediate for the synthesis of chiral oxazoline alcohol ligands and the synthesis of chiral imidazolidines.","abstract_has_math":false,"creators":["Noël, Timothy"],"institution":"Ghent University. Faculty of Sciences","degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":null,"school":null,"contributors":["Van der Eycken, Johan"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2009,"date_issued":"2009","date_published":"2009","updated_at":"2026-07-24T02:23:03Z","subjects":["Chemistry","P_N ligands","diene ligands","Imidate ligands","Asymmetric catalysis","Ligand Design"],"languages":["eng"],"rights":["info:eu-repo/semantics/openAccess"],"rights_urls":[],"identifier_entries":[{"key":"dc:identifier","label":"Identifier","values":["https://biblio.ugent.be/publication/811200","https://biblio.ugent.be/publication/811200/file/4335096"],"render_values":[{"text":"https://biblio.ugent.be/publication/811200","href":"https://biblio.ugent.be/publication/811200","code":true},{"text":"https://biblio.ugent.be/publication/811200/file/4335096","href":"https://biblio.ugent.be/publication/811200/file/4335096","code":true}]}]},"links":{"outbound_url":"http://hdl.handle.net/1854/LU-811200","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Van der Eycken, Johan"]},{"key":"dc:creator","label":"Author","values":["Noël, Timothy"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2009"]},{"key":"dc:publisher","label":"Institution","values":["Ghent University. 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We developed a novel route to synthesize chiral disubstituted bicyclo[2.2.1]heptadienes (R= i-Bu, c-Hex, Benzyl and allyl) starting from enantiomerically pure bistriflate. The synthesized diene ligands were tested in the rhodium(I)-catalyzed 1,4-addition of phenylboronic acids to cyclic enones (up to 96% ee) and α-acetamido acrylic ester and in the rhodium(I)-catalyzed 1,2-addition of phenylboronic acids to benzaldehydes (up to 48% ee). We introduced chiral imidates as a novel nitrogen-based ligand family. These imidates, with an exocyclic nitrogen, have never before been reported in literature. We showed that these imidate ligands could be obtained readily via a one-step synthesis starting from a central precursor in excellent yields. Moreover, imidate ligands could further be fine-tuned when substituents were put on the aromatic ring of the imidate ligand precursor. The synthesized monodentate and bidentate ligands were tested in several asymmetric test reactions. In the copper(I)-catalyzed asymmetric aziridinations, we obtained usually high yields (up to 90% yield) and moderate enantioselectivity (51% ee) with a bidentate imidate ligand. The asymmetric addition of diethylzinc to benzaldehyde resulted in high yields (up to 87% yield) and good enantioselectivities (up to 76% ee). However, the best result was obtained in the asymmetric allylic alkylation with an imidate with a binaphtylbackbone: a moderate yield (53% yield) with an excellent selectivity (95% ee). Futhermore, we developed successfully hybrid imidate-phosphane ligands as a new type of P,N ligands. These ligands are easily accessible in one step via a condensation of a commercially available aminophosphane and an imidate ligand precursor. The ligands were demonstrated to be highly valuable in palladium-catalyzed allylic substitution reactions. Excellent performance of this catalyst system was observed in the allylic alkylation of 1,3-diphenyl-2-propenyl acetate with various nucleophiles (up to 99% yield and >99% ee). Moreover, the allylic alkylation of linear unhindered and cyclic substrates resulted in good conversions and enantioselectivities. The cyclic imidate ligand precursor could also be used efficiently as a synthetic intermediate for the synthesis of chiral oxazoline alcohol ligands and the synthesis of chiral imidazolidines."]},{"key":"dc:format","label":"Dc Format","values":["application/pdf"]},{"key":"dc:title","label":"Title","values":["Synthesis and application of chiral dienes and chiral imidates as ligands for transition metal catalysis"]}]}],"canonical_facts":{"dc:contributor":["Van der Eycken, Johan"],"dc:creator":["Noël, Timothy"],"dc:date":["2009"],"dc:description":["In this dissertation, two main ligandclasses have been studied: chiral diene ligands and chiral imidate ligands. We developed a novel route to synthesize chiral disubstituted bicyclo[2.2.1]heptadienes (R= i-Bu, c-Hex, Benzyl and allyl) starting from enantiomerically pure bistriflate. The synthesized diene ligands were tested in the rhodium(I)-catalyzed 1,4-addition of phenylboronic acids to cyclic enones (up to 96% ee) and α-acetamido acrylic ester and in the rhodium(I)-catalyzed 1,2-addition of phenylboronic acids to benzaldehydes (up to 48% ee). We introduced chiral imidates as a novel nitrogen-based ligand family. These imidates, with an exocyclic nitrogen, have never before been reported in literature. We showed that these imidate ligands could be obtained readily via a one-step synthesis starting from a central precursor in excellent yields. Moreover, imidate ligands could further be fine-tuned when substituents were put on the aromatic ring of the imidate ligand precursor. The synthesized monodentate and bidentate ligands were tested in several asymmetric test reactions. In the copper(I)-catalyzed asymmetric aziridinations, we obtained usually high yields (up to 90% yield) and moderate enantioselectivity (51% ee) with a bidentate imidate ligand. The asymmetric addition of diethylzinc to benzaldehyde resulted in high yields (up to 87% yield) and good enantioselectivities (up to 76% ee). However, the best result was obtained in the asymmetric allylic alkylation with an imidate with a binaphtylbackbone: a moderate yield (53% yield) with an excellent selectivity (95% ee). Futhermore, we developed successfully hybrid imidate-phosphane ligands as a new type of P,N ligands. These ligands are easily accessible in one step via a condensation of a commercially available aminophosphane and an imidate ligand precursor. The ligands were demonstrated to be highly valuable in palladium-catalyzed allylic substitution reactions. Excellent performance of this catalyst system was observed in the allylic alkylation of 1,3-diphenyl-2-propenyl acetate with various nucleophiles (up to 99% yield and >99% ee). Moreover, the allylic alkylation of linear unhindered and cyclic substrates resulted in good conversions and enantioselectivities. The cyclic imidate ligand precursor could also be used efficiently as a synthetic intermediate for the synthesis of chiral oxazoline alcohol ligands and the synthesis of chiral imidazolidines."],"dc:format":["application/pdf"],"dc:identifier":["https://biblio.ugent.be/publication/811200","http://hdl.handle.net/1854/LU-811200","https://biblio.ugent.be/publication/811200/file/4335096"],"dc:language":["eng"],"dc:publisher":["Ghent University. Faculty of Sciences"],"dc:rights":["info:eu-repo/semantics/openAccess"],"dc:subject":["Chemistry","P_N ligands","diene ligands","Imidate ligands","Asymmetric catalysis","Ligand Design"],"dc:title":["Synthesis and application of chiral dienes and chiral imidates as ligands for transition metal catalysis"],"dc:type":["dissertation","info:eu-repo/semantics/doctoralThesis","info:eu-repo/semantics/publishedVersion"]},"updated_at":"2026-07-24T02:23:03Z"}