Formation of an Oxidant-Sensible Pd(II) Coordination Compound and Its 1H NMR Specific Characterization: A Preparative and Analytical Challenge in Current Coordination Chemistry

Maria L. Abraham; Iris M. Oppel

doi:10.1021/ed500447f

Formation of an Oxidant-Sensible Pd(II) Coordination Compound and Its 1H NMR Specific Characterization: A Preparative and Analytical Challenge in Current Coordination Chemistry

Journal of Chemical Education ◽

10.1021/ed500447f ◽

2014 ◽

Vol 91 (12) ◽

pp. 2174-2177 ◽

Cited By ~ 2

Author(s):

Maria L. Abraham ◽

Iris M. Oppel

Keyword(s):

Coordination Chemistry ◽

1H Nmr ◽

Coordination Compound ◽

Analytical Challenge

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SYNTHESIS AND SPECTRAL PROPERTIES OF LANTANIDE COMPLEXES WITH A NEW TRIPODAL TRIS-CHELATING CAPh LIGAND

Bulletin of Taras Shevchenko National University of Kyiv Chemistry ◽

10.17721/1728-2209.2018.1(55).8 ◽

2018 ◽

pp. 35-39

Author(s):

M. Strugatska ◽

I. Olyshevets ◽

V. Ovchynnikov ◽

V. Amirkhanov

Keyword(s):

Mass Loss ◽

Coordination Number ◽

1H Nmr ◽

Coordination Compound ◽

Strong Field ◽

Electronic Spectroscopy ◽

Lanthanide Ions ◽

Exothermic Effect ◽

Gravimetric Analysis ◽

Electronic Density

A new tripodal tris-chelating carbacylamidophosphate (CAPh) ligand (H3L = N(CH2CH2N(H)C(O)N(H)P(O)(OCH3)2)3) has been synthesized and a series of coordination compounds of general formula LnL (where Ln = La, Nd, Eu, Tb) based on this ligand has been obtained and isolated in the crystalline state. The resulting compounds have been investigated by the means of thermal gravimetric analysis, 1H NMR, IR and UV-Vis absorption spectroscopy. The ligand and all complexes are soluble in water, poorly soluble in methanol and isopropanol, insoluble in nonpolar solvents. It was found, that each Ln(III) ion of the complexes under consideration is bonded with oxygen atoms belonging to the phosphoryl and carboxyl groups of three bidentate chelated coordinating arms of the ligand (six lanthanide-oxygen bonds totally). In the 1H NMR spectrum of lanthanum coordination compound (LnL) all signals are shifted in the region of a strong field compared to analogous signals in the respective H3L spectrum, which can be explained by the redistribution of electronic density in the ligand due to deprotonation. The fine structure of the supersensitive transitions in the electronic spectrum of the synthesized neodymium complex proves in favor of the coordination number 8. In the region of 4I9/2 → 2P1/2 transition (425–435 nm) a single absorption band is observed, indicating the presence of only one absorption center. The thermal stability of NdL complex has been investigated and the presence of two coordinated water molecules in the synthesized complexes has been established. Thus, coordination number of lanthanide ions is equal to eight (coordination formula [LnL(H2O)2]) which is in agreement with electronic spectroscopy results. Based on the data of the TGA for the coordination compound [NdL(H2O)2] one can conclude that significant mass loss occurs in one step. The complex compound begins to decompose above 200°C. Considerable mass loss continues to a temperature of 380–400°С. The DTA curve shows an exothermic effect at a temperature of 287°C, which can be connected with the oxidation processes.

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The Triple-Decker Complex [Cp*Fe(µ,η5:η5-P5)Mo(CO)3] as a Building Block in Coordination Chemistry

Molecules ◽

10.3390/molecules24020325 ◽

2019 ◽

Vol 24 (2) ◽

pp. 325

Author(s):

Mehdi Elsayed Moussa ◽

Stefan Welsch ◽

Luis Dütsch ◽

Martin Piesch ◽

Stephan Reichl ◽

...

Keyword(s):

Coordination Chemistry ◽

Transition Metal ◽

Supramolecular Chemistry ◽

Coordination Compound ◽

Building Block ◽

Fluorine Atom ◽

Metal Compounds ◽

X Ray ◽

New Perspective ◽

Selective Formation

Although the triple-decker complex [Cp*Fe(µ,η5:η5-P5)Mo(CO)3] (2) was first reported 26 years ago, its reactivity has not yet been explored. Herein, we report a new high-yielding synthesis of 2 and the isolation of its new polymorph (2’). In addition, we study its reactivity towards AgI and CuI ions. The reaction of 2 with Ag[BF4] selectively produces the coordination compound [Ag{Cp*Fe(µ,η5:η5-P5)Mo(CO)3}2][BF4] (3). Its reaction with Ag[TEF] and Cu[TEF] ([TEF]− = [Al{OC(CF3)3}4]−) leads to the selective formation of the complexes [Ag{Cp*Fe(µ,η5:η5-P5)Mo(CO)3}2][TEF] (4) and [Cu{Cp*Fe(µ,η5:η5-P5)Mo(CO)3}2][TEF] (5), respectively. The X-ray structures of compounds 3–5 each show an MI ion (MI = AgI, CuI) bridged by two P atoms from two triple-decker complexes (2). Additionally, four short MI···CO distances (two to each triple-decker complex 2) participate in stabilizing the coordination sphere of the MI ion. Evidently, the X-ray structure for compound 3 shows a weak interaction of the AgI ion with one fluorine atom of the counterion [BF4]−. Such an Ag···F interaction does not exist for compound 4. These findings demonstrate the possibility of using triple-decker complex 2 as a ligand in coordination chemistry and opening a new perspective in the field of supramolecular chemistry of transition metal compounds with phosphorus-rich complexes.

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