Bis-Cyclometalated Indazole and Benzimidazole Chiral-at-Iridium Complexes: Synthesis and Asymmetric Catalysis
A new class of bis-cyclometalated iridium(III) catalysts containing two inert cyclometalated 6-<i>tert</i>-butyl-2-phenyl-2<i>H</i>-indazole bidentate ligands or two inert cyclometalated 5-<i>tert</i>-butyl-1-methyl-2-phenylbenzimidazoles is introduced. The coordi...
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| Format: | Article |
| Language: | English |
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MDPI AG
2021-03-01
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| Series: | Molecules |
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| Online Access: | https://www.mdpi.com/1420-3049/26/7/1822 |
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| author | Sebastian Brunen Yvonne Grell Philipp S. Steinlandt Klaus Harms Eric Meggers |
| author_facet | Sebastian Brunen Yvonne Grell Philipp S. Steinlandt Klaus Harms Eric Meggers |
| author_sort | Sebastian Brunen |
| collection | DOAJ |
| description | A new class of bis-cyclometalated iridium(III) catalysts containing two inert cyclometalated 6-<i>tert</i>-butyl-2-phenyl-2<i>H</i>-indazole bidentate ligands or two inert cyclometalated 5-<i>tert</i>-butyl-1-methyl-2-phenylbenzimidazoles is introduced. The coordination sphere is complemented by two labile acetonitriles, and a hexafluorophosphate ion serves as a counterion for the monocationic complexes. Single enantiomers of the chiral-at-iridium complexes (>99% er) are obtained through a chiral-auxiliary-mediated approach using a monofluorinated salicyloxazoline and are investigated as catalysts in the enantioselective conjugate addition of indole to an α,β-unsaturated 2-acyl imidazole and an asymmetric Nazarov cyclization. |
| first_indexed | 2024-03-10T12:57:04Z |
| format | Article |
| id | doaj.art-6a1f6e7bdff247a3ac30d88a5d02ecb8 |
| institution | Directory Open Access Journal |
| issn | 1420-3049 |
| language | English |
| last_indexed | 2024-03-10T12:57:04Z |
| publishDate | 2021-03-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Molecules |
| spelling | doaj.art-6a1f6e7bdff247a3ac30d88a5d02ecb82023-11-21T11:48:16ZengMDPI AGMolecules1420-30492021-03-01267182210.3390/molecules26071822Bis-Cyclometalated Indazole and Benzimidazole Chiral-at-Iridium Complexes: Synthesis and Asymmetric CatalysisSebastian Brunen0Yvonne Grell1Philipp S. Steinlandt2Klaus Harms3Eric Meggers4Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Strasse 4, 35043 Marburg, GermanyFachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Strasse 4, 35043 Marburg, GermanyFachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Strasse 4, 35043 Marburg, GermanyFachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Strasse 4, 35043 Marburg, GermanyFachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Strasse 4, 35043 Marburg, GermanyA new class of bis-cyclometalated iridium(III) catalysts containing two inert cyclometalated 6-<i>tert</i>-butyl-2-phenyl-2<i>H</i>-indazole bidentate ligands or two inert cyclometalated 5-<i>tert</i>-butyl-1-methyl-2-phenylbenzimidazoles is introduced. The coordination sphere is complemented by two labile acetonitriles, and a hexafluorophosphate ion serves as a counterion for the monocationic complexes. Single enantiomers of the chiral-at-iridium complexes (>99% er) are obtained through a chiral-auxiliary-mediated approach using a monofluorinated salicyloxazoline and are investigated as catalysts in the enantioselective conjugate addition of indole to an α,β-unsaturated 2-acyl imidazole and an asymmetric Nazarov cyclization.https://www.mdpi.com/1420-3049/26/7/1822cyclometalationchiral-at-metalasymmetric catalysis |
| spellingShingle | Sebastian Brunen Yvonne Grell Philipp S. Steinlandt Klaus Harms Eric Meggers Bis-Cyclometalated Indazole and Benzimidazole Chiral-at-Iridium Complexes: Synthesis and Asymmetric Catalysis Molecules cyclometalation chiral-at-metal asymmetric catalysis |
| title | Bis-Cyclometalated Indazole and Benzimidazole Chiral-at-Iridium Complexes: Synthesis and Asymmetric Catalysis |
| title_full | Bis-Cyclometalated Indazole and Benzimidazole Chiral-at-Iridium Complexes: Synthesis and Asymmetric Catalysis |
| title_fullStr | Bis-Cyclometalated Indazole and Benzimidazole Chiral-at-Iridium Complexes: Synthesis and Asymmetric Catalysis |
| title_full_unstemmed | Bis-Cyclometalated Indazole and Benzimidazole Chiral-at-Iridium Complexes: Synthesis and Asymmetric Catalysis |
| title_short | Bis-Cyclometalated Indazole and Benzimidazole Chiral-at-Iridium Complexes: Synthesis and Asymmetric Catalysis |
| title_sort | bis cyclometalated indazole and benzimidazole chiral at iridium complexes synthesis and asymmetric catalysis |
| topic | cyclometalation chiral-at-metal asymmetric catalysis |
| url | https://www.mdpi.com/1420-3049/26/7/1822 |
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