Transition-Metal Complexes with Sterically Demanding Ligands: Facile Thermal Intermolecular CH Bond Activation in a Square-Planar IrI Complex

2003 ◽  
Vol 42 (14) ◽  
pp. 1632-1636 ◽  
Author(s):  
Stefan Nückel ◽  
Peter Burger
Keyword(s):  
Transition Metal ◽  
Metal Complexes ◽  
Transition Metal Complexes ◽  
Bond Activation ◽  
Square Planar ◽  
Sterically Demanding

Recent Advances in Transition Metal Catalyzed C-H Functionalization Reactions Involving Aza/Oxabicyclic Alkenes

Synthesis ◽  
2021 ◽  
Author(s):  
Masilamani Jeganmohan ◽  
Pinki Sihag
Keyword(s):  
Transition Metal ◽  
Metal Complexes ◽  
Transition Metal Complexes ◽  
Ring Opening ◽  
Bond Activation ◽  
Considerable Progress ◽  
Double Bonds ◽  
Facial Selectivity ◽  
Ring Opening Reactions ◽  
Metal Catalyzed

Bicyclic alkenes, including Oxa- and azabicyclic alkenes can be readily activated by using transition-metal complexes with facial selectivity, because of the intrinsic angle strain on carbon-carbon double bonds of these unsymmetrical bicyclic systems. During last decades considerable progress has been done in the area of ring-opening of bicyclic strained ring by employing the concept of C-H activation. This Review comprehensively compiles the various C-H bond activation assisted reactions of oxa- and azabicyclic alkenes, viz., ring-opening reactions, hydroarylation as well as annulation reactions.

scholarly journals The Exchange of Cyclometalated Ligands

Molecules ◽  
2021 ◽  
Vol 26 (1) ◽  
pp. 210
Author(s):  
Alexander D. Ryabov
Keyword(s):  
Transition Metal ◽  
Metal Complexes ◽  
Transition Metal Complexes ◽  
Bond Activation ◽  
Bond Cleavage ◽  
Cyclopalladated Complexes ◽  
Derivatives Of ◽  
Cyclometalated Ligand ◽  
Incoming Ligand

Reactions of cyclometalated compounds are numerous. This account is focused on one of such reactions, the exchange of cyclometalated ligands, a reaction between a cyclometalated compound and an incoming ligand that replaces a previously cyclometalated ligand to form a new metalacycle: + H-C*~Z ⇄ + H-C~Y. Originally discovered for PdII complexes with Y/Z = N, P, S, the exchange appeared to be a mechanistically challenging, simple, and convenient routine for the synthesis of cyclopalladated complexes. Over four decades it was expanded to cyclometalated derivatives of platinum, ruthenium, manganese, rhodium, and iridium. The exchange, which is also questionably referred to as transcyclometalation, offers attractive synthetic possibilities and assists in disclosing key mechanistic pathways associated with the C–H bond activation by transition metal complexes and C–M bond cleavage. Both synthetic and mechanistic aspects of the exchange are reviewed and discussed.

CO2 reduction catalysis by tunable square-planar transition-metal complexes: a theoretical investigation using nitrogen-substituted carbon nanotube models

2017 ◽  
Vol 19 (43) ◽  
pp. 29068-29076 ◽  
Author(s):  
Yu-Te Chan ◽  
Ming-Kang Tsai
Keyword(s):  
Density Functional Theory ◽  
Carbon Nanotube ◽  
Transition Metal ◽  
Metal Complexes ◽  
Transition Metal Complexes ◽  
Density Functional ◽  
Co2 Reduction ◽  
Functional Theory ◽  
Square Planar ◽  
Planar Transition

The CO2 reduction capabilities of transition-metal-chelated nitrogen-substituted carbon nanotube models (TM-4N2v-CNT, TM = Fe, Ru, Os, Co, Rh, Ir, Ni, Pt or Cu) are characterized by density functional theory.

Übergangsmetallkomplexe mit Schwefelliganden, LXXVI Redox- und Additionsreaktionen von Nickelkomplexen mehrzähniger Thioether-Thiolat-Liganden. Röntgenstrukturanalysen von (NMe4)2[Ni(′S2′)2] und [Ni(′S4 – C3′)(PMe3)] / Transition Metal Complexes with Sulfur Ligands, LXXVI Redox and Addition Reactions of Nickel Complexes with Multidentate Thioether-Thiolato Ligands. X-Ray Structure Determinations of (NMe4)2[Ni(′S2′)2] and [Ni(′S4–C3′)(PMe3)]

1991 ◽  
Vol 46 (12) ◽  
pp. 1601-1608 ◽  
Author(s):  
Dieter Sellmann ◽  
Stefan Fünfgelder ◽  
Falk Knoch ◽  
Matthias Moll
Keyword(s):  
Transition Metal ◽  
Metal Complexes ◽  
Structure Analysis ◽  
Transition Metal Complexes ◽  
Nickel Complexes ◽  
Addition Reactions ◽  
Coordination Geometry ◽  
X Ray ◽  
Square Planar ◽  
Structure Determinations

In order to elucidate specific properties of nickel sulfur complexes, redox and addition-elimination reactions of [Ni(′OS4')]2, [Ni(′NHS4')]2, [Ni(′S5')], [Ni('S4—C5')], and [Ni('S4—C3')] were investigated ('OS4′ 2' = 2,2'-bis(2-mercaptophenylthio)diethylether(2—), 'NHS4'2- = 2,2'-bis(2-mercaptophenylthio)diethylamine(2—), 'S5'2- = 2,2'-bis(2-mercaptophenylthio)diethylsulfide(2—), 'S4-C5'2- = 1,5-bis(2-mercaptophenylthio)pentane(2—), 'S4—C3'2- = 1,3-bis(2-mercaptophenylthio)propane(2—)).Cyclovoltammetry proves the complexes to be redox inactive between —1.4 and +0.8 V vs. NHE. Above +0.8 V the complexes are irreversibly oxidized, below —1,4 V desalkylation takes place and [Ni(′S,′)2]2- is formed. An X-ray structure analysis was carried out of (NMe4)2[Ni(′S2')2], which shows a planar anion with the Ni center in a nearly perfect square planar coordination. Distances and angles are practically identical to those in the [Ni(′S2')2-] monoanion.The complexes coordinate only phosphines as coligands, but thioether donors simultaneously decoordinate and, dependant of reaction temperature, mono- or trisphosphine complexes are formed. [Ni(′S4—C3')(PMe3)] was characterized by X-ray structure analysis and exhibits a square pyramidal coordination geometry.

scholarly journals Transition metal complexes of 5-bromosalicylidene-4-amino-3-mercapto-1,2,4-triazine-5-one: Synthesis, characterization, catalytic and antibacterial studies

2011 ◽  
Vol 76 (1) ◽  
pp. 75-83 ◽  
Author(s):  
A.S. Ramasubramanian ◽  
Ramachandra Bhat ◽  
Ramakrishna Dileep ◽  
Sandya Rani
Keyword(s):  
Transition Metal ◽  
Metal Complexes ◽  
Transition Metal Complexes ◽  
Pathogenic Bacteria ◽  
Magnetic Moments ◽  
Spectroscopic Techniques ◽  
Antibacterial Studies ◽  
Metal Precursors ◽  
Square Planar ◽  
Bactericidal Properties

Transition metal complexes of 5-bromosalicylidene-4-amino-3- mercapto-1,2,4-triazine-5-one with metal precursors, such as Cu(II), Ni(II), Co(II) and Pd(II), were synthesized and characterized by physicochemical and spectroscopic techniques. All the complexes are of the ML type. Based on analytical, spectral data and magnetic moments, the Co(II) and Ni(II) complexes were assigned octahedral geometries, while the Cu (II) and Pd(II) complexes square planar. A study on the catalytic oxidation of benzyl alcohol, cyclohexanol, cinnamyl alcohol, 2-propanol and 2- methyl-1-propanol was performed with N-methylmorpholine-N-oxide (NMO) and molecular oxygen as co-oxidants. All the complexes and their parent organic moiety were screened for their biological activity on several pathogenic bacteria and were found to possess appreciable bactericidal properties.

scholarly journals Transition metal complexes with thiosemicarbazide-based ligands. Part 60. Reactions of copper(II) bromide with pyridoxal S-methylisothiosemicarbazone (PLITSC). Crystal structure of [Cu(PLITSC−H)H2O]Br•H2O

2014 ◽  
Vol 79 (3) ◽  
pp. 291-302 ◽  
Author(s):  
Vukadin Leovac ◽  
Ljiljana Vojinovic-Jesic ◽  
Sonja Ivkovic ◽  
Marko Rodic ◽  
Ljiljana Jovanovic ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Thermal Analysis ◽  
Transition Metal ◽  
Metal Complexes ◽  
Transition Metal Complexes ◽  
Elemental Analysis ◽  
Structural Characterization ◽  
Electronic Spectra ◽  
Square Planar

The synthesis and structural characterization of a square-planar copper(II) complex with pyridoxal S-methylisothiosemicarbazone (PLITSC) of the formula [Cu(PLITSC?H)H2O]Br?H2O (1) as the first Cu(II) complex with monoanionic form of this ligand were described. Complex 1 together with two previously synthesized complexes [Cu(PLITSC)Br2] (2) and [Cu(PLITSC)Br(MeOH)]Br (3) were characterized by elemental analysis, IR and electronic spectra and also by the methods of thermal analysis, conductometry and magnetochemistry.

Kinetic trans effect in square planar transition metal complexes

1974 ◽  
Vol 96 (13) ◽  
pp. 4121-4125 ◽  
Author(s):  
L. G. Vanquickenborne ◽  
J. Vranckx ◽  
C. Goeller-Walrand
Keyword(s):  
Transition Metal ◽  
Metal Complexes ◽  
Transition Metal Complexes ◽  
Trans Effect ◽  
Square Planar ◽  
Planar Transition

Transition Metal Complexes of [2-{Di(m-tolyl)phosphino}ethyl]diphenylphosphine

1979 ◽  
Vol 32 (5) ◽  
pp. 1143 ◽  
Author(s):  
ND Sadanani ◽  
A Walia ◽  
PN Kapoor ◽  
RN Kapoor
Keyword(s):  
Transition Metal ◽  
Metal Complexes ◽  
Transition Metal Complexes ◽  
Electrical Conductance ◽  
Metal Carbonyls ◽  
Spectral Measurements ◽  
Element Analysis ◽  
Magnetic Susceptibilities ◽  
Conductance Data ◽  
Square Planar

The 1 : 1 complexes of chelating diphosphine, [2-{di(m-tolyl)phosphino}ethyl]diphenylphosphine (pmtpf), with nickel(II), palladium(II) and platinum(II) halides and thiocyanates and 2 : 1 complexes with nickel(II) perchlorates have been prepared. Ligand (pmtpf) forms low-spin square-planar and diamagnetic [M(pmtpf)X2](where X = Cl, Br, I or NCS; M = Ni, Pd or Pt) and [Ni(pmtpf)2]- (ClO4)2 complexes. Complexes of metal carbonyls having the general formula [(pmtpf)M(CO)4] (where M = Cr, Mo or W) have also been synthesized. These complexes have been characterized on the basis of element analysis, electronic, infrared and 1H N.M.R. spectral measurements, magnetic susceptibilities and electrical conductance data. In all cases studied this ligand acts as a chelating ditertiary phosphine.

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