Azaphilic versus carbophilic coupling at C=N bonds: key steps in titanium-assisted multicomponent reactions
Abstract Consecutive C- and N-arylation of N-heterocyclic nitriles is mediated by titanium(IV) alkoxides. The carbo- and azaphilic arylation step may be separated by choosing the order in which the two equivalents of aryl transfer reagent are added. In the course of this transformation, the ancillar...
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| Hauptverfasser: | , , , |
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| Dokumenttyp: | Article (Journal) |
| Sprache: | Englisch |
| Veröffentlicht: |
[2015]
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| In: |
Chemistry - a European journal
Year: 2015, Jahrgang: 21, Heft: 51, Pages: 18730-18738 |
| ISSN: | 1521-3765 |
| DOI: | 10.1002/chem.201503732 |
| Online-Zugang: | Verlag, lizenzpflichtig, Volltext: https://doi.org/10.1002/chem.201503732 Verlag, lizenzpflichtig, Volltext: https://chemistry-europe.onlinelibrary.wiley.com/doi/full/10.1002/chem.201503732 
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| Verfasserangaben: | Torsten Roth, Hubert Wadepohl, Eric Clot, and Lutz H. Gade |
| Zusammenfassung: | Abstract Consecutive C- and N-arylation of N-heterocyclic nitriles is mediated by titanium(IV) alkoxides. The carbo- and azaphilic arylation step may be separated by choosing the order in which the two equivalents of aryl transfer reagent are added. In the course of this transformation, the ancillary N-heterocycle acts as both a directing anchor group and electron reservoir. In the selectivity-determining step, the selectivity is governed by a choice between (direct) C- and Ti-arylation; the latter opens up a reaction pathway that allows further migration to the nitrogen atom. The isolation of metal-containing aggregates from the reaction mixture and computational studies gave insights into the reaction mechanism. Subsequently, a multicomponent one-pot protocol was devised to rapidly access complex quaternary carbon centers. |
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| Beschreibung: | Gesehen am 08.07.2020 |
| Beschreibung: | Online Resource |
| ISSN: | 1521-3765 |
| DOI: | 10.1002/chem.201503732 |