Stabilization of η3-indenyl compounds by sterically demanding N,N-chelating ligands in the molybdenum coordination sphere

A series of η3-indenyl molybdenum compounds, isostructural with the well-known η3-allyl compounds, was synthesized from the recently established synthon [{(η5-4,7-Me2C9H5)Mo(CO)2(μ-Cl)}2].

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Organophosphines in organoplatinum complexes: structural aspects of trans-PtP2C2 derivatives

Reviews in Inorganic Chemistry ◽

10.1515/revic-2016-0003 ◽

2017 ◽

Vol 37 (1) ◽

pp. 1-10

Author(s):

Milan Melník ◽

Peter Mikuš

Keyword(s):

Coordination Sphere ◽

Coordination Mode ◽

Structural Parameters ◽

Donor Ligands ◽

Chelating Ligands ◽

Mean Values ◽

Structural Aspects

AbstractThis review summarized and analyzed the structural parameters of 174 monomeric organoplatinum complexes with an inner coordination sphere of trans-PtP2C2. These complexes crystallized in four crystal systems: hexagonal (x2), orthorhombic (x13), triclinic (x76), and monoclinic (x84). These complexes, on the basis of the coordination mode of the respective donor ligands, can be divided into the seven sub-groups: Pt(PL)2(CL)2, Pt(PL)2(η2-C2L), Pt(η2-P2L)(CL)2, Pt(PL)(η2-P,CL)(CL), Pt(η2-P,CL)2, Pt(η3-P,C,PL)(CL), and Pt(η3-C,P,CL)(PL). The chelating ligands create 4-, 5-, 6-, 16-, 17-, 18-, and 19-membered rings. The total mean values of Pt-L bond distances are 2.055 Å (C) and 2.300 Å (P). There are examples that exist in two isomeric forms and are examples of distortion isomerism. The structural parameters of trans-PtP2C2 are discussed with those of cis-PtP2C2 derivatives.

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Synthesis, reactivity and characterization of Pt(ii) complexes with N,N′ chelating ligands; structure and dimethylsulfoxide reactivity relationship

Dalton Transactions ◽

10.1039/c6dt04035g ◽

2017 ◽

Vol 46 (5) ◽

pp. 1467-1480 ◽

Cited By ~ 6

Author(s):

Konstantinos Ypsilantis ◽

Theodoros Tsolis ◽

Andreas Kourtellaris ◽

Manolis J. Manos ◽

John C. Plakatouras ◽

...

Keyword(s):

Coordination Sphere ◽

Chelating Ligands ◽

Square Planar

Chelated N-heterocycles can be replaced from the coordination sphere of square planar Pt(ii) complexes by DMSO.

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Incorporation of non-planar chelating ligands in the coordination sphere of ruthenium(II) complexes

Inorganica Chimica Acta ◽

10.1016/s0020-1693(00)00343-1 ◽

2001 ◽

Vol 313 (1-2) ◽

pp. 43-55 ◽

Cited By ~ 27

Author(s):

Rosario Scopelliti ◽

Giuseppe Bruno ◽

Caterina Donato ◽

Giuseppe Tresoldi

Keyword(s):

Coordination Sphere ◽

Chelating Ligands

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Organophosphines in PtP4 derivatives; structural aspects

Reviews in Inorganic Chemistry ◽

10.1515/revic-2018-0025 ◽

2019 ◽

Vol 39 (3) ◽

pp. 129-137

Author(s):

Milan Melník ◽

Peter Mikuš

Keyword(s):

Coordination Sphere ◽

Coordination Mode ◽

Covalent Bond ◽

Structural Data ◽

Coordination Complexes ◽

Chelating Ligands ◽

Mean Values ◽

Structural Aspects

AbstractIn this review, we classify and analyze the structural data of more than 80 monomeric platinum coordination complexes with an inner coordination sphere of PtP4 in which only organophosphines are involved. On the basis of the coordination mode of respective organophosphines, these complexes can be divided into six subgroups: Pt(PL)4, Pt(PL)2(PL′)2, Pt(η2-P2L)(PL)2, Pt(η2-P2L)2, Pt(η2-P2L)(η2-P2L′)2, and Pt(η4-P4L). The chelating ligands forming wide varieties of metallocycles: (P=P), (PNP), (PCP), (PC2P), (PP2P), (PC2NP), (PNCNP), (PNPNP), (POHOP), (POBOP), (PCNCP), (PC3P), (PC4P), and (PC2OC2P). The effects of both steric and electronic factors reflect on the values of P-Pt-P chelate angles. The total mean values of Pt-P elongate in the order: 2.289 Å (tetradentate)<2.306 Å (monodentate)<2.320 Å (bidentate). The same order shows the respective covalent bond weaknesses.

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Regioselective Gas-Phase n-Butane Transfer Dehydrogenation via Silica-Supported Pincer-Iridium Complexes

10.26434/chemrxiv.12885491.v1 ◽

2020 ◽

Author(s):

Boris Sheludko ◽

Cristina Castro ◽

Chaitanya Khalap ◽

Thomas Emge ◽

Alan Goldman ◽

...

Keyword(s):

Gas Phase ◽

Active Site ◽

Lower Cost ◽

Open Systems ◽

Iridium Complexes ◽

Terminal Olefin ◽

Molecular Precursors ◽

Sterically Demanding ◽

Olefin Production ◽

Steam Cracking

Abstract: The production of olefins via on-purpose dehydrogenation of alkanes allows for a more efficient, selective and lower cost alternative to processes such as steam cracking. Silica-supported pincer-iridium complexes of the form [(≡SiO-R4POCOP)Ir(CO)] (R4POCOP = κ3-C6H3-2,6-(OPR2)2) are effective for acceptorless alkane dehydrogenation, and have been shown stable up to 300 °C. However, while solution-phase analogues of such species have demonstrated high regioselectivity for terminal olefin production under transfer dehydrogenation conditions at or below 240 °C, in open systems at 300 °C, regioselectivity under acceptorless dehydrogenation conditions is consistently low. In this work, complexes <a>[(≡SiO-tBu4POCOP)Ir(CO)] </a>(1) and [(≡SiO-iPr4PCP)Ir(CO)] (2) were synthesized via immobilization of molecular precursors. These complexes were used for gas-phase butane transfer dehydrogenation using increasingly sterically demanding olefins, resulting in observed selectivities of up to 77%. The results indicate that the active site is conserved upon immobilization.

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Ethylene Polymerization by Monochloro Non-Bridged Half-Metallocene-type Zirconium Complexes Containing Phosphine Oxide-(thio)phenolate Chelating Ligands as Catalyst at High Temperature

ACTA AGRONOMICA SINICA ◽

10.3724/sp.j.1095.2013.30198 ◽

2013 ◽

Vol 30 (11) ◽

pp. 1293

Author(s):

Sanrong LIU ◽

Jingyu LIU ◽

Yuesheng LI

Keyword(s):

High Temperature ◽

Phosphine Oxide ◽

Ethylene Polymerization ◽

Chelating Ligands ◽

Zirconium Complexes

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Monodentate Trialkylphosphines: Privileged Ligands in Metal-catalyzed Crosscoupling Reactions

Current Organic Chemistry ◽

10.2174/1385272824666200211114540 ◽

2020 ◽

Vol 24 (3) ◽

pp. 231-264 ◽

Cited By ~ 3

Author(s):

Kevin H. Shaughnessy

Keyword(s):

Transition Metal ◽

Cross Coupling ◽

Coupling Reactions ◽

Cross Coupling Reactions ◽

Aryl Bromides ◽

Wide Range ◽

Sterically Demanding ◽

Transition Metal Catalyzed ◽

Catalyzed Reactions ◽

Metal Catalyzed

Phosphines are widely used ligands in transition metal-catalyzed reactions. Arylphosphines, such as triphenylphosphine, were among the first phosphines to show broad utility in catalysis. Beginning in the late 1990s, sterically demanding and electronrich trialkylphosphines began to receive attention as supporting ligands. These ligands were found to be particularly effective at promoting oxidative addition in cross-coupling of aryl halides. With electron-rich, sterically demanding ligands, such as tri-tertbutylphosphine, coupling of aryl bromides could be achieved at room temperature. More importantly, the less reactive, but more broadly available, aryl chlorides became accessible substrates. Tri-tert-butylphosphine has become a privileged ligand that has found application in a wide range of late transition-metal catalyzed coupling reactions. This success has led to the use of numerous monodentate trialkylphosphines in cross-coupling reactions. This review will discuss the general properties and features of monodentate trialkylphosphines and their application in cross-coupling reactions of C–X and C–H bonds.

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Coordination state of cobalt(II) ions in solution and on a sulphonated organic polymer

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19792330 ◽

1979 ◽

Vol 44 (8) ◽

pp. 2330-2337 ◽

Cited By ~ 1

Author(s):

Jindřiška Maternová ◽

Anastas A. Andreev ◽

Dimitrii M. Shopov ◽

Karel Setínek

Keyword(s):

Acetic Acid ◽

Coordination Sphere ◽

Glacial Acetic Acid ◽

Organic Polymer ◽

Octahedral Complex ◽

Coordination State ◽

Tetrahedral Symmetry ◽

Liquid Acid ◽

Homogeneous Phase ◽

Bromide Ion

It was found spectroscopically that cobalt(II) acetate dissolved in glacial acetic acid forms the octahedral complex [Co(OAc)2(HOAc)4] which in the presence of bromide ions gives the octahedral [Co(OAc)Br(HOAc)4] and tetrahedral bromo(acetate)cobalt(II) complexes with the higher number of Br- ions. When attached to an organic polymer cobalt(II) ions are bonded in the form of octahedral [Co(H2O)6]2+ cations which form with acetic acid similar complexes as in homogeneous phase and are able to coordinate one bromide ion. Drying the copolymer possessing octahedral hexaaquocobalt(II) cations leads to tetrahedral aquocomplexes which are solvated by gaseous acetic acid and converted into the acetate complexes with the liquid acid. The latter contain the acid in the inner coordination sphere and have tetrahedral symmetry.

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Photooxidation effect of cupric complexes on aliphatic alcohols in nonaqueous solutions

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19822061 ◽

1982 ◽

Vol 47 (8) ◽

pp. 2061-2068 ◽

Cited By ~ 13

Author(s):

Jan Sýkora ◽

Mária Jakubcová ◽

Zuzana Cvengrošová

Keyword(s):

Coordination Sphere ◽

Alcohol Oxidation ◽

Aliphatic Alcohols ◽

Oxidation Products ◽

Molar Ratio ◽

Quantum Yields ◽

Nonaqueous Solutions ◽

The Absolute ◽

Absolute Quantum

In the photolysis of copper(II)-chloride-alcohol-acetonitrile systems (cCu = 1 mmol l-1, copper(II)-to-chloride molar ratio 1 : 2 to 1 : 8, 10% (v/v) alcohol), Cu(II) is reduced to Cu(I), and methanol, ethanol, 1-propanol, or 1-butanol is oxidized to the corresponding aldehyde, 2-propanol to acetone. In the case of 1-propanol and 1-butanol, chlorinated aldehydes are formed in addition too. The measured quantum yields of the photoreduction of Cu(II) to Cu(I) lay in the range of ΦCu(I) = 4.5 to 40 mmol einstein-1, the absolute quantum yields of the alcohol oxidation products were 2.3 to 47 mmol einstein-1. The photoactive components are chlorocupric complexes [CuClx](2-x)+ (x = 1-4). The presence of complexes with a higher number of chloroligands in the coordination sphere (x = 3, 4) brings about a decrease in the Cu(II) photoreduction rate. The decrease in the photoreduction rate observed in the presence of dioxygen is explained in terms of re-oxidation of copper(I) by the latter, resulting in an increase in the concentration of the photochemically active cupric complexes. The catalytic aspects of the systems in question are discussed with respect to this effect.

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Complexes of copper(II) and nickel(II) with a Schiff base bonded to a polymeric support

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19832021 ◽

1983 ◽

Vol 48 (7) ◽

pp. 2021-2027 ◽

Cited By ~ 9

Author(s):

Eliška Kálalová ◽

Olga Populová ◽

Štěpánka Štokrová ◽

Pavel Stopka

Keyword(s):

Magnetic Properties ◽

Schiff Base ◽

Coordination Sphere ◽

Polymer Matrix ◽

Glycidyl Methacrylate ◽

Epr Spectra ◽

Polymeric Support ◽

Tetrahedral Configuration ◽

Paramagnetic Complexes

Copper(II) and nickel(II) ions were bonded in complexes of salicylideneimine type on a glycidyl methacrylate-ethylenedimethacrylate copolymer. The geometry of the complexes on the polymer was studied by measuring their magnetic properties, EPR spectra, and ultraviolet-visible spectra.Only paramagnetic complexes possessing a pseudo-tetrahedral configuration were found. The effect of the polymer matrix and of the immobility of the bonded Schiff base on the distortion of the coordination sphere of the central ion is discussed.

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