The reaction of an oxime ester with [Ru(PPh ) X ] proceeded smoothly at room temperature to afford a stable Ru ketimido complex as oxidative adduct. The structure of the complex was unambiguously determined by X-ray crystallographic analysis, which showed an almost linear Ru-N-C array. The electronic properties of the nitrogen atom were estimated by DFT calculations, and the results suggested double-bond character of the Ru-N bond. Kinetic studies and consideration of the substituent effect on the oxime ester led to the proposal of a reaction mechanism involving oxidative addition, which could proceed by N,O-chelating coordination to the Ru center prior to N-O bond cleavage. The obtained Ru ketimido complex could be transformed into a ruthenacycle by C-H activation by a concerted metalation-deprotonation mechanism in dichloromethane/methanol. Ru ketimido complexes with a tethered alkyne or alkene moiety underwent chloroamination of unsaturated C-C bonds followed by C-H activation, which resulted in the formation of a ruthenacycle. Considering the LUMO of an isolated Ru ketimido complex, the chloroamination should proceed by a synchronous 1,3-dipolar cycloaddition-type mechanism. Insight into the character and reactivity of Ru ketimido complexes will be helpful for developments in the catalytic transformation of oxime esters.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1002/chem.201704102 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Manganese-Pincer-Catalyzed Nitrile Hydration, α-Deuteration, and α-Deuterated Amide Formation via Metal Ligand Cooperation.
ACS Catal
August 2021
Department of Molecular Chemistry and Materials Science and Chemical Research Support, Weizmann Institute of Science, Rehovot 76100, Israel.
A simple and efficient system for the hydration and α-deuteration of nitriles to form amides, α-deuterated nitriles, and α-deuterated amides catalyzed by a single pincer complex of the earth-abundant manganese capable of metal-ligand cooperation is reported. The reaction is selective and tolerates a wide range of functional groups, giving the corresponding amides in moderate to good yields. Changing the solvent from -butanol to toluene and using DO results in formation of α-deuterated nitriles in high selectivity.
View Article and Find Full Text PDFTemplate catalysis by manganese pincer complexes: oxa- and aza-Michael additions to unsaturated nitriles.
Chem Sci
October 2019
Department of Organic Chemistry , The Weizmann Institute of Science, Rehovot 76100 , Israel . Email:
Activation of C[triple bond, length as m-dash]N bonds by metal-ligand cooperation provides a new route for the functionalization of nitriles. Herein, we report the electrophilic activation of unsaturated nitriles by dearomatized manganese pincer complexes for the oxa- and aza-Michael addition reactions under very mild and neutral conditions. Derivatives of acrylonitrile and allyl cyanide furnished the corresponding β-addition products by reacting with alcohols and amines.
View Article and Find Full Text PDFPreparation of Heterobimetallic Ketimido-Actinide-Molybdenum Complexes.
Inorg Chem
October 2019
Department of Chemistry , The University of Manchester, Oxford Road , Manchester , M13 9PL , United Kingdom.
During our attempts to prepare paddlewheel actinide-molybdenum complexes of the type [(X)An(MesNPR)Mo(CO)] (Mes= 2,4,6-trimethylphenyl; X = Cl or I; An = U or Th; R = Pr or Ph) we have found that under certain conditions acetonitrile insertion reactions occur to give the heterobimetallic bridging ketimido species [ClAn(μ-MesNPPr)(μ-MesNPPr{μ-NCMe})Mo(CO)] (An = U, ; Th, ), [ClAn(μ-MesNPPh)(μ-MesNPPh{μ-NCMe})Mo(CO)] (An = U, ; An = Th, ), and [IAn(η-MesNPPr)(μ-MesNPPr){μ-NC(Me)N(Mes)PPr}Mo(CO)] (An = U, ; Th, ). Structural and spectroscopic data confirm the assignment of a ketimido ligand bridging An(IV) and Mo(0) centers. The isolation of - is in contrast to our previously reported preparations of [(X)An(MesNPPh)Mo(CO)] (An = U or Th; X= Cl or I; , , 13515-13518) with the difference in reactivity being attributable to a combination of ancillary phosphino-amide, reaction solvent, and temperature variation.
View Article and Find Full Text PDFGeneration of Stable Ruthenium(IV) Ketimido Complexes by Oxidative Addition of Oxime Esters to Ruthenium(II): Reactivity Studies Based on Electronic Properties of the Ru-N Bond.
Chemistry
November 2017
Department of Energy and Hydrocarbon Chemistry, Graduate School of Engineering, Kyoto University, Nishikyo-ku, Kyoto, 615-8510, Japan.
The reaction of an oxime ester with [Ru(PPh ) X ] proceeded smoothly at room temperature to afford a stable Ru ketimido complex as oxidative adduct. The structure of the complex was unambiguously determined by X-ray crystallographic analysis, which showed an almost linear Ru-N-C array. The electronic properties of the nitrogen atom were estimated by DFT calculations, and the results suggested double-bond character of the Ru-N bond.
View Article and Find Full Text PDFMetal-ligand cooperative activation of nitriles by a ruthenium complex with a de-aromatized PNN pincer ligand.
Dalton Trans
October 2016
Stratingh Institute for Chemistry, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands.
The pincer complex (PNN)RuH(CO), with a de-aromatized pyridine in the ligand backbone, is shown to react with nitriles in a metal-ligand cooperative manner. This leads to the formation of a series of complexes with new Ru-N(nitrile) and C(ligand)-C(nitrile) bonds. The initial nitrile cycloaddition products, the ketimido complexes 3, have a Brønsted basic (nitrile-derived) Ru-N fragment.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!