Developing P-Stereogenic, Planar Chiral P-Alkene Ligands: Monodentate, Bidentate, and Double Agostic Coordination Modes on Ru(II)

Beitrag in einer Fachzeitschrift


Details zur Publikation

Autor(en): Herrera AC, Grasruck A, Heinemann F, Scheurer A, Chelouan A, Frierss S, Seidel F, Dorta R
Zeitschrift: Organometallics
Verlag: AMER CHEMICAL SOC
Jahr der Veröffentlichung: 2017
Band: 36
Heftnummer: 3
Seitenbereich: 714-720
ISSN: 0276-7333


Abstract

10-Phenyl-5H-dibenz[b,f]azepine (5) is synthesized by Suzuki cross coupling of the protected bromo alkene 4 with PhB(OH)(2). 5 reacts with PCl3 to afford the dichlorophosphanyl-azepine 6 in >90% yield. Alkylation of 6 with 1 equiv of t-BuMgBr leads, after recrystallization in Et2O, to the diastereomerically enriched (dr > 98:2) chloride rac-7, which the crystal structure reveals to be the (pS,R-P)/(pR,S-P) pair. The fact that rac-7 crystallizes in the Sohncke space group P2(1)2(1)2(1) opens up the possibility of a mechanical separation of the enantiomers. Methylation of rac-7 is perfectly stereoselective with inversion of configuration at the P atom to yield the new ligand rac-8 as the (R,R)/(S,S) pair. The corresponding BH3-protected diastereomer rac-9 (i.e., the (R,S)/(S,R) pair), is isolated after flash column chromatography in 73% yield. Compounds 59 are accessible in multigram quantities. X-ray crystal structures of Ru(II) complexes demonstrate the ambidentate nature of ligand rac-8: Complex 10 is exclusively P-coordinated, while in complex 11 two ligands bind Ru through their P donors and stabilize the 14-electron metal center with a double agostic interaction. In complex 12, the ligand coordinates in a kappa P,eta(2)-alkene bidentate fashion.


FAU-Autoren / FAU-Herausgeber

Chelouan, Ahmed Dr.
Lehrstuhl für Anorganische und Allgemeine Chemie
Dorta, Romano Prof. Dr.
Professur für Anorganische Chemie
Grasruck, Alexander
Lehrstuhl für Anorganische und Allgemeine Chemie
Heinemann, Frank Dr.
Lehrstuhl für Anorganische und Allgemeine Chemie
Scheurer, Andreas Dr.
Lehrstuhl für Anorganische und Allgemeine Chemie
Seidel, Falk
Lehrstuhl für Anorganische und Allgemeine Chemie


Zitierweisen

APA:
Herrera, A.C., Grasruck, A., Heinemann, F., Scheurer, A., Chelouan, A., Frierss, S.,... Dorta, R. (2017). Developing P-Stereogenic, Planar Chiral P-Alkene Ligands: Monodentate, Bidentate, and Double Agostic Coordination Modes on Ru(II). Organometallics, 36(3), 714-720. https://dx.doi.org/10.1021/acs.organomet.6b00879

MLA:
Herrera, Alberto Cesar, et al. "Developing P-Stereogenic, Planar Chiral P-Alkene Ligands: Monodentate, Bidentate, and Double Agostic Coordination Modes on Ru(II)." Organometallics 36.3 (2017): 714-720.

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Zuletzt aktualisiert 2018-06-07 um 08:23