Reactions of a pincer proligand with copper iodide: bridging instead of C–H metalation

Various precursors of divalent copper have been treated with the meta-disubstituted phenylene-based proligand POC(H)OP (1,3-(i-Pr2PO)2C6H4) with the objective of preparing classical pincer complexes (POCOP)CuX. However, in no case was such species obtained, presumably owing to the difficult C–H metallation step. Analogous reactions of monovalent precursors were also unsuccessful, whereas reaction of POC(H)OP with CuI under different conditions gave the non-metallated adducts {(μ, κP, [Formula: see text]-POC(H)OP)Cu(μ-Ι)}2, 1, {(μ, κP, [Formula: see text]-POC(H)OP)Cu2(μ-Ι)2(DMAP)2}, 2 (DMAP = 4-dimethylaminopyridine), and {(μ, κP, [Formula: see text]-POC(H)OP)Cu2(μ3-Ι)2}2, 3. Treating 1 with DMAP gave the adduct 2, whereas 3 could be obtained by treating 1 with BuLi or by sublimation of 1. The solid state structures of these complexes revealed the tetrahedral geometry that might be anticipated for the d10 Cu(I) centers, in addition to fairly close I–H distances; on the other hand, no C–H interaction (agostic or otherwise) was observed with the Cu centers in any of these structures. The unsuccessful metallation of the C(2)–H moiety is thought to be a result of the strong preference of monovalent copper center to form bridging interactions with iodide and the POC(H)OP ligand; this appears to prevent the approach of the central carbon of the ligand to the Cu centers.

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The Solid-State Structures of Cyclic NH Carboximides

Crystals ◽

10.3390/cryst10070606 ◽

2020 ◽

Vol 10 (7) ◽

pp. 606

Author(s):

R. Aitken ◽

Dheirya Sonecha

Keyword(s):

Solid State ◽

Functional Groups ◽

The Other ◽

X Ray Diffraction ◽

Cyclic Imide ◽

X Ray ◽

Solid State Structures

The patterns adopted in the solid state structures of over 300 cyclic NH carboximides as determined by X-ray diffraction are reviewed. While the analysis shows that the majority of these fit into just a few common patterns, a significant number exhibit more complex and interesting patterns involving the other functional groups present in addition to the cyclic imide.

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Synthesis, crystal structures and electrochemistry of ferrocenyl-substituted 1,3,4-oxadiazoles

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc2010064 ◽

2010 ◽

Vol 75 (10) ◽

pp. 1023-1040 ◽

Cited By ~ 5

Author(s):

Jiří Tauchman ◽

Jakub Trnka ◽

Ivana Císařová ◽

Petr Štěpnička

Keyword(s):

Solid State ◽

Diffraction Analysis ◽

Electronic Communication ◽

The Other ◽

Spectroscopic Methods ◽

Redox Behavior ◽

X Ray Diffraction ◽

X Ray ◽

Elemental Analyses ◽

Solid State Structures

Two ferrocenyl-substituted 1,3,4-oxadiazoles, 2-ferrocenyl-1,3,4-oxadiazole (1) and 2,5-diferrocenyl-1,3,4-oxadiazole (2), have been prepared from the corresponding hydrazides, (ferrocenecarbonyl)hydrazine (3) and 1,2-bis(ferrocenecarbonyl)hydrazine (4), and characterized by conventional spectroscopic methods (IR, NMR, MS) and elemental analyses. The solid-state structures of 1, 2 and 4 have been determined by single-crystal X-ray diffraction analysis. The redox behavior of 1 and 2 was studied by electrochemical methods. Compound 1 underwent a reversible one-electron oxidation attributed to the ferrocene/ ferrocenium couple (Eo′ = +0.28 V vs ferrocene/ferrocenium). On the other hand, compound 2 showed two closely separated anodic waves corresponding to two consecutive redox changes, indicating some degree of electronic communication between the ferrocenyl moieties in positions 2 and 5 at the 1,3,4-oxadiazole ring.

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Water-soluble NNN-pincer complexes of cobalt, nickel and palladium: Solid-state structures and catalytic activity

Polyhedron ◽

10.1016/j.poly.2017.09.027 ◽

2018 ◽

Vol 143 ◽

pp. 138-143 ◽

Cited By ~ 8

Author(s):

Joshua Heidebrecht ◽

Chris Gendy ◽

Benjamin S. Gelfand ◽

Roland Roesler

Keyword(s):

Catalytic Activity ◽

Solid State ◽

Water Soluble ◽

Pincer Complexes ◽

Cobalt Nickel ◽

Solid State Structures

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Interaction of Charged Particle Beams with Electrostatic Oscillations in Cylindrical Solid-State Structures

Telecommunications and Radio Engineering ◽

10.1615/telecomradeng.v55.i10-11.190 ◽

2001 ◽

Vol 55 (10-11) ◽

pp. 9 ◽

Cited By ~ 1

Author(s):

A. F. Rusanov ◽

Vladimir M. Yakovenko

Keyword(s):

Charged Particle ◽

Solid State ◽

Particle Beams ◽

Charged Particle Beams ◽

Cylindrical Solid ◽

Solid State Structures

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Effect of Hydrated Metal Salts on the Coordination Product of Cobalt(II) halide and PNP Type Ligand, 2,6-bis(di-tertbutylphosphinomethyl) pyridine

10.26434/chemrxiv.5851701 ◽

2018 ◽

Author(s):

Tasneem Siddiquee ◽

Abdul Goni

Keyword(s):

Metal Salts ◽

Molar Ratio ◽

Pincer Complexes ◽

Asymmetric Unit ◽

X Ray Diffraction ◽

Pincer Ligand ◽

Tetrahedral Geometry ◽

X Ray ◽

Distorted Tetrahedral Geometry ◽

Cobalt Center

Chemical treatment of CoX2. 6H2O (X = Cl, Br, I) with the potentially tridentate PNP pincer ligand 2,6-bis(di-tert-butylphosphinomethyl)pyridine in 1:1 molar ratio results in cobalt(II) halide-PNP pincer complexes. The effect of the hydrated metal source on molecular structure and geometry of the complexes was studied by single crystal X-ray diffraction analysis. The complexes are neutral and the cobalt center adopts a penta-coordinate system with potential atropisomerization. Within the unit cell there are two distinct molecules per asymmetric unit. One of the two phosphorus atoms in the PNP ligand was observed to be partially oxidized to phosphinoxide. Disorder in the structure reflects a mixture of square pyramidal and distorted tetrahedral geometry.

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Spectroscopic, X-ray Diffraction and Density Functional Theory Study of Intra- and Intermolecular Hydrogen Bonds in Ortho-(4-tolylsulfonamido)benzamides

Molecules ◽

10.3390/molecules26040926 ◽

2021 ◽

Vol 26 (4) ◽

pp. 926

Author(s):

Malose J. Mphahlele ◽

Eugene E. Onwu ◽

Marole M. Maluleka

Keyword(s):

Density Functional Theory ◽

Solid State ◽

Hydrogen Bonds ◽

Density Functional ◽

Tetrahedral Geometry ◽

Hindered Rotation ◽

Hydrogen Bond Acceptor ◽

Functional Theory ◽

Vis Spectroscopy ◽

Hydrogen Bonded

The conformations of the title compounds were determined in solution (NMR and UV-Vis spectroscopy) and in the solid state (FT-IR and XRD), complemented with density functional theory (DFT) in the gas phase. The nonequivalence of the amide protons of these compounds due to the hindered rotation of the C(O)–NH2 single bond resulted in two distinct resonances of different chemical shift values in the aromatic region of their 1H-NMR spectra. Intramolecular hydrogen bonding interactions between the carbonyl oxygen and the sulfonamide hydrogen atom were observed in the solution phase and solid state. XRD confirmed the ability of the amide moiety of this class of compounds to function as a hydrogen bond acceptor to form a six-membered hydrogen bonded ring and a donor simultaneously to form intermolecular hydrogen bonded complexes of the type N–H···O=S. The distorted tetrahedral geometry of the sulfur atom resulted in a deviation of the sulfonamide moiety from co-planarity of the anthranilamide scaffold, and this geometry enabled oxygen atoms to form hydrogen bonds in higher dimensions.

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