Homo- and Heteropolynuclear Platinum Complexes Stabilized by Dimethylpyrazolato and Alkynyl Bridging Ligands: Synthesis, Structures, and Luminescence

Juan Forniés; Sara Fuertes; Antonio Martín; Violeta Sicilia; Elena Lalinde; M. Teresa Moreno

doi:10.1002/chem.200600139

Platinum complexes having redox-active PPh2CCFc and/or CCFc as terminal or bridging ligands

Dalton Transactions ◽

10.1039/b822171e ◽

2009 ◽

pp. 3434 ◽

Cited By ~ 19

Author(s):

Álvaro Díez ◽

Elena Lalinde ◽

M. Teresa Moreno ◽

Sergio Sánchez

Keyword(s):

Platinum Complexes ◽

Bridging Ligands ◽

Redox Active

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Tuning the Redox Activity of Metal−Organic Frameworks for Enhanced, Selective O2 Binding

10.26434/chemrxiv.10316681.v1 ◽

2019 ◽

Author(s):

Andrew Rosen ◽

M. Rasel Mian ◽

Timur Islamoglu ◽

Haoyuan Chen ◽

Omar Farha ◽

...

Keyword(s):

Density Functional ◽

Metal Organic Frameworks ◽

Redox Activity ◽

Screening Methods ◽

Bridging Ligands ◽

Metal Centers ◽

Computational Screening ◽

Open Metal Sites ◽

Metal Organic ◽

Unsaturated Metal Sites

Metal−organic frameworks (MOFs) with coordinatively unsaturated metal sites are appealing as adsorbent materials due to their tunable functionality and ability to selectively bind small molecules. Through the use of computational screening methods based on periodic density functional theory, we investigate O2 and N2 adsorption at the coordinatively unsaturated metal sites of several MOF families. A variety of design handles are identified that can be used to modify the redox activity of the metal centers, including changing the functionalization of the linkers (replacing oxido donors with sulfido donors), anion exchange of bridging ligands (considering μ-Br-, μ-Cl-, μ-F-, μ-SH-, or μ-OH- groups), and altering the formal oxidation state of the metal. As a result, we show that it is possible to tune the O2 affinity at the open metal sites of MOFs for applications involving the strong and/or selective binding of O2. In contrast with O2 adsorption, N2 adsorption at open metal sites is predicted to be relatively weak across the MOF dataset, with the exception of MOFs containing synthetically elusive V2+ open metal sites. As one example from the screening study, we predict that exchanging the μ-Cl- ligands of M2Cl2(BBTA) (H2BBTA = 1H,5H-benzo(1,2-d:4,5-d′)bistriazole) with μ-OH- groups would significantly enhance the strength of O2 adsorption at the open metal sites without a corresponding increase in the N2 affinity. Experimental investigation of Co2Cl2(BBTA) and Co2(OH)2(BBTA) confirms that the former exhibits only weak physisorption, whereas the latter is capable of chemisorbing O2 at room temperature. The chemisorption behavior is attributed to the greater electron-donating character of the μ-OH- ligands and the presence of H-bonding interactions between the μ-OH- bridging ligands and the O2 adsorbate.

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Exchange-Biasing in a Dinuclear Dysprosium(III) Single-Molecule Magnet with a Large Energy Barrier for Magnetization Reversal

10.26434/chemrxiv.10260494 ◽

2019 ◽

Author(s):

Tian Han ◽

Marcus J. Giansiracusa ◽

Zi-Han Li ◽

You-Song Ding ◽

Nicholas F. Chilton ◽

...

Keyword(s):

Single Molecule ◽

Magnetization Reversal ◽

Energy Barrier ◽

Magnetic Hysteresis ◽

Large Energy ◽

Magnetic Studies ◽

Bridging Ligands ◽

Single Molecule Magnet ◽

Exchange Biasing

A dichlorido-bridged dinuclear dysprosium(III) single-molecule magnet [Dy2L2(µ-Cl)2(THF)2] has been made using a diamine-bis(phenolate) ligand, H2L. Magnetic studies show an energy barrier for magnetization reversal (Ueff) around 1000 K. Exchange-biasing effect is clearly seen in magnetic hysteresis with steps up to 4 K. Ab initio calculations exclude the possibility of pure dipolar origin of this effect leading to the conclusion that super-exchange via the chloride bridging ligands is important.

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The binding of neutral platinum complexes by crown ethers. X-Ray crystal structures of [trans-PtCl2(PMe3)NH3˙dibenzo-18-crown-6] and [{trans-PtCl2(PMe3)NH3}2·18-crown-6]

Journal of the Chemical Society Chemical Communications ◽

10.1039/c39810000847 ◽

1981 ◽

Vol 0 (16) ◽

pp. 847-849 ◽

Cited By ~ 16

Author(s):

Howard M. Colquhoun ◽

J. Fraser Stoddart ◽

David J. Williams

Keyword(s):

Crystal Structures ◽

Crown Ethers ◽

Platinum Complexes ◽

X Ray

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First Attempts of the Use of 195Pt NMR of Phenylbenzothiazole Complexes as Spectroscopic Technique for the Cancer Diagnosis

Molecules ◽

10.3390/molecules24213970 ◽

2019 ◽

Vol 24 (21) ◽

pp. 3970 ◽

Cited By ~ 1

Author(s):

Bruna T. L. Pereira ◽

Mateus A. Gonçalves ◽

Daiana T. Mancini ◽

Kamil Kuca ◽

Teodorico C. Ramalho

Keyword(s):

Cancer Treatment ◽

Cancer Diagnosis ◽

Density Functional ◽

Chemical Shifts ◽

Chloride Ion ◽

Platinum Complexes ◽

Dft Method ◽

Ion Concentration ◽

Implicit Solvent ◽

Early Cancer Diagnosis

Platinum complexes have been studied for cancer treatment for several decades. Furthermore, another important platinum characteristic is related to its chemical shifts, in which some studies have shown that the 195Pt chemical shifts are very sensitive to the environment, coordination sphere, and oxidation state. Based on this relevant feature, Pt complexes can be proposed as potential probes for NMR spectroscopy, as the chemical shifts values will be different in different tissues (healthy and damaged) Therefore, in this paper, the main goal was to investigate the behavior of Pt chemical shifts in the different environments. Calculations were carried out in vacuum, implicit solvent, and inside the active site of P13K enzyme, which is related with breast cancer, using the density functional theory (DFT) method. Moreover, the investigation of platinum complexes with a selective moiety can contribute to early cancer diagnosis. Accordingly, the Pt complexes selected for this study presented a selective moiety, the 2-(4′aminophenyl)benzothiazole derivative. More specifically, two Pt complexes were used herein: One containing chlorine ligands and one containing water in place of chlorine. Some studies have shown that platinum complexes coordinated to chlorine atoms may suffer hydrolyses inside the cell due to the low chloride ion concentration. Thus, the same calculations were performed for both complexes. The results showed that both complexes presented different chemical shift values in the different proposed environments. Therefore, this paper shows that platinum complexes can be a potential probe in biological systems, and they should be studied not only for cancer treatment, but also for diagnosis.

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Molecular structures and magnetic properties of .mu.-phenolato binuclear copper(II) complexes incorporating chloro, hydroxo, and azido exogenous bridging ligands

Inorganic Chemistry ◽

10.1021/ic00294a008 ◽

1988 ◽

Vol 27 (21) ◽

pp. 3710-3716 ◽

Cited By ~ 34

Author(s):

Azdine Benzekri ◽

Patrick Dubourdeaux ◽

Jean Marc Latour ◽

Jean Laugier ◽

Paul Rey

Keyword(s):

Magnetic Properties ◽

Molecular Structures ◽

Binuclear Copper ◽

Bridging Ligands

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ChemInform Abstract: The Dynamic Behavior of η3-Allyl Palladium and Platinum Complexes Containing the SnCl3 Ligand.

ChemInform ◽

10.1002/chin.198805042 ◽

1988 ◽

Vol 19 (5) ◽

Author(s):

M. GIANOTTI ◽

A. MUSCO ◽

M. SISTI ◽

M. GRASSI ◽

G. GATTI

Keyword(s):

Dynamic Behavior ◽

Platinum Complexes ◽

Palladium And Platinum Complexes

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3D Metal–Organic Frameworks Based on Co(II) and Bithiophendicarboxylate: Synthesis, Crystal Structures, Gas Adsorption, and Magnetic Properties

Molecules ◽

10.3390/molecules26051269 ◽

2021 ◽

Vol 26 (5) ◽

pp. 1269

Author(s):

Vadim A. Dubskikh ◽

Anna A. Lysova ◽

Denis G. Samsonenko ◽

Alexander N. Lavrov ◽

Konstantin A. Kovalenko ◽

...

Keyword(s):

Room Temperature ◽

Gas Adsorption ◽

Magnetic Moments ◽

Bet Surface Area ◽

Separation Performance ◽

Bridging Ligands ◽

Magnetization Data ◽

Metal Organic ◽

Ch4 Adsorption ◽

Gas Separation Performance

Three new 3D metal-organic porous frameworks based on Co(II) and 2,2′-bithiophen-5,5′-dicarboxylate (btdc2−) [Co3(btdc)3(bpy)2]·4DMF, 1; [Co3(btdc)3(pz)(dmf)2]·4DMF·1.5H2O, 2; [Co3(btdc)3(dmf)4]∙2DMF∙2H2O, 3 (bpy = 2,2′-bipyridyl, pz = pyrazine, dmf = N,N-dimethylformamide) were synthesized and structurally characterized. All compounds share the same trinuclear carboxylate building units {Co3(RCOO)6}, connected either by btdc2– ligands (1, 3) or by both btdc2– and pz bridging ligands (2). The permanent porosity of 1 was confirmed by N2, O2, CO, CO2, CH4 adsorption measurements at various temperatures (77 K, 273 K, 298 K), resulted in BET surface area 667 m2⋅g−1 and promising gas separation performance with selectivity factors up to 35.7 for CO2/N2, 45.4 for CO2/O2, 20.8 for CO2/CO, and 4.8 for CO2/CH4. The molar magnetic susceptibilities χp(T) were measured for 1 and 2 in the temperature range 1.77–330 K at magnetic fields up to 10 kOe. The room-temperature values of the effective magnetic moments for compounds 1 and 2 are μeff (300 K) ≈ 4.93 μB. The obtained results confirm the mainly paramagnetic nature of both compounds with some antiferromagnetic interactions at low-temperatures T < 20 K in 2 between the Co(II) cations separated by short pz linkers. Similar conclusions were also derived from the field-depending magnetization data of 1 and 2.

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