Palladium complexes based on ylide-functionalized phosphines (YPhos)
- Palladium allyl, cinnamyl, and indenyl complexes with the ylide‐substituted phosphines \(Cy_{3}P^{+}−C^{−}(R)PCy_{2}\) (with R=Me (\(\bf L1\)) or Ph (\(\bf L2\))) and \(Cy_{3}P^{+}−C^{−}(Me)P\)\(\it t\)Bu\(_2\) (\(\bf L3\)) were prepared and applied as defined precatalysts in C−N coupling reactions. The complexes are highly active in the amination of 4‐chlorotoluene with a series of different amines. Higher yields were observed with the precatalysts in comparison to the in situ generated catalysts. Changes in the ligand structures allowed for improved selectivities by shutting down β‐hydride elimination or diarylation reactions. Particularly, the complexes based on \(\bf L2\) (joYPhos) revealed to be universal precatalysts for various amines and aryl halides. Full conversions to the desired products are reached mostly within 1 h reaction time at room temperature, thus making \(\bf L2\) to one of the most efficient ligands in C−N coupling reactions. The applicability of the catalysts was demonstrated for aryl chlorides, bromides and iodides together with primary and secondary aryl and alkyl amines, including gram‐scale applications also with low catalyst loadings of down to 0.05 mol %. Kinetic studies further demonstrated the outstanding activity of the precatalysts with TOF over 10.000 h\(^{−1}\).
Author: | Jens TappenGND, Ilja RodsteinGND, Katie McGuireGND, Angela GroßjohannGND, Julian LöfflerGND, Thorsten ScherpfGND, Viktoria H. Däschlein-GessnerORCiDGND |
---|---|
URN: | urn:nbn:de:hbz:294-80476 |
DOI: | https://doi.org/10.1002/chem.201905535 |
Parent Title (English): | Chemistry - a European Journal |
Subtitle (English): | broadly applicable high-performance precatalysts for the amination of aryl halides at room temperature |
Publisher: | Wiley-VCH Verlag |
Place of publication: | Weinheim |
Document Type: | Article |
Language: | English |
Date of Publication (online): | 2021/04/28 |
Date of first Publication: | 2020/01/23 |
Publishing Institution: | Ruhr-Universität Bochum, Universitätsbibliothek |
Tag: | coupling reactions; ligand design; palladium; phosphines; structure - activity relationship |
Volume: | 26 |
Issue: | 19 |
First Page: | 4281 |
Last Page: | 4288 |
Note: | Dieser Beitrag ist auf Grund des DEAL-Wiley-Vertrages frei zugänglich. |
Institutes/Facilities: | Lehrstuhl für Anorganische Chemie II |
Dewey Decimal Classification: | Naturwissenschaften und Mathematik / Chemie, Kristallographie, Mineralogie |
open_access (DINI-Set): | open_access |
faculties: | Fakultät für Chemie und Biochemie |
Licence (English): | Creative Commons - CC BY-NC 4.0 - Attribution-NonCommercial 4.0 International |