| Publikationstyp: | Beitrag in wissenschaftlicher Zeitschrift |
| Art der Begutachtung: | Peer review (Publikation) |
| Titel: | Chirality transfer in an Ireland-Claisen rearrangement : a new approach toward the Iboga alkaloids |
| Autor/-in: | Höck, Stefan Koch, Florian Borschberg, Hans-Jürg |
| DOI: | 10.1016/j.tetasy.2004.04.028 |
| Erschienen in: | Tetrahedron: Asymmetry |
| Band(Heft): | 15 |
| Heft: | 11 |
| Seite(n): | 1801 |
| Seiten bis: | 1808 |
| Erscheinungsdatum: | 2004 |
| Verlag / Hrsg. Institution: | Elsevier |
| ISSN: | 0957-4166 1362-511X |
| Sprache: | Englisch |
| Schlagwörter: | Indole alkaloids; Chirality transfer; Ireland-Claisen rearrangemenent |
| Fachgebiet (DDC): | 572: Biochemie |
| Zusammenfassung: | The synthesis of the isoquinuclidine core of the Iboga alkaloid family is described. This building block contains the entire stereochemical information of the targeted natural products. Starting with (S)-4-(hydroxymethyl)-4-butanolide, a derivative available in two steps from l-glutamate, (S)-4-benzyloxy-5,5-dimethoxypentanoic acid was obtained in four steps. Mitsunobu esterification with (S)-but-3-en-2-ol furnished the inverted ester, which was then subjected to an Ireland–Claisen rearrangement. This crucial step took place with a very satisfactory chirality transfer from the alcohol component to the new carbon backbone of the product. After transformation of the resulting silyl ester function into a hydroxylamino group, the dimethyl acetal moiety was hydrolyzed with 3 M sulfuric acid at 47°C. Under these conditions, the resulting cyclic nitrone could not be isolated, because it underwent a rapid intramolecular nitrone–olefin [3+2]-cycloaddition reaction to furnish the expected tricyclic isoxazolidine derivative in 67% yield. After chromatographic purification, this product was obtained enantiomerically pure and with a chemical purity of 96%. The targeted isoquinuclidine building block was thus obtained from (S)-4-(hydroxymethyl)-4-butanolide in 13 steps with an overall yield of 9.2%, which amounts to an average yield of 83.3% per step. |
| URI: | https://digitalcollection.zhaw.ch/handle/11475/11998 |
| Volltext Version: | Publizierte Version |
| Lizenz (gemäss Verlagsvertrag): | Lizenz gemäss Verlagsvertrag |
| Departement: | Life Sciences und Facility Management |
| Organisationseinheit: | Institut für Chemie und Biotechnologie (ICBT) |
| Enthalten in den Sammlungen: | Publikationen Life Sciences und Facility Management |
Dateien zu dieser Ressource:
Es gibt keine Dateien zu dieser Ressource.
Zur Langanzeige
Höck, S., Koch, F., & Borschberg, H.-J. (2004). Chirality transfer in an Ireland-Claisen rearrangement : a new approach toward the Iboga alkaloids. Tetrahedron: Asymmetry, 15(11), 1801–1808. https://doi.org/10.1016/j.tetasy.2004.04.028
Höck, S., Koch, F. and Borschberg, H.-J. (2004) ‘Chirality transfer in an Ireland-Claisen rearrangement : a new approach toward the Iboga alkaloids’, Tetrahedron: Asymmetry, 15(11), pp. 1801–1808. Available at: https://doi.org/10.1016/j.tetasy.2004.04.028.
S. Höck, F. Koch, and H.-J. Borschberg, “Chirality transfer in an Ireland-Claisen rearrangement : a new approach toward the Iboga alkaloids,” Tetrahedron: Asymmetry, vol. 15, no. 11, pp. 1801–1808, 2004, doi: 10.1016/j.tetasy.2004.04.028.
HÖCK, Stefan, Florian KOCH und Hans-Jürg BORSCHBERG, 2004. Chirality transfer in an Ireland-Claisen rearrangement : a new approach toward the Iboga alkaloids. Tetrahedron: Asymmetry. 2004. Bd. 15, Nr. 11, S. 1801–1808. DOI 10.1016/j.tetasy.2004.04.028
Höck, Stefan, Florian Koch, and Hans-Jürg Borschberg. 2004. “Chirality Transfer in an Ireland-Claisen Rearrangement : A New Approach toward the Iboga Alkaloids.” Tetrahedron: Asymmetry 15 (11): 1801–8. https://doi.org/10.1016/j.tetasy.2004.04.028.
Höck, Stefan, et al. “Chirality Transfer in an Ireland-Claisen Rearrangement : A New Approach toward the Iboga Alkaloids.” Tetrahedron: Asymmetry, vol. 15, no. 11, 2004, pp. 1801–8, https://doi.org/10.1016/j.tetasy.2004.04.028.
Alle Ressourcen in diesem Repository sind urheberrechtlich geschützt, soweit nicht anderweitig angezeigt.