Synthesis and Investigations of the Antitumor Effects of First-Row Transition Metal(II) Complexes Supported by Two Fluorinated and Non-Fluorinated β-Diketonates.

The 3 transition metal (Mn(II), Fe(II), Co(II), Ni(II), Cu(II) and Zn(II)) complexes, supported by anions of sterically demanding β-diketones, 1,3-dimesitylpropane-1,3-dione (HL) and 1,3-bis(3,5-bis(trifluoromethyl)phenyl)-3-hydroxyprop-2-en-1-one (HL), were synthesized and evaluated for their antitumor activity. To assess the biological effects of substituents on phenyl moieties, we also synthesized and investigated the analogous metal(II) complexes of the anion of the less bulky 1,3-diphenylpropane-1,3-dione (HL) ligand. The compounds [Cu(L)], [Cu(L)] and ([Zn(L)]) were characterized by X-ray crystallography.

Correction: When SF outplays CF: effects of pentafluorosulfanyl decorated scorpionates on copper.

[This corrects the article DOI: 10.1039/D1SC04846E.].

Understanding Copper(I)-Ethylene Bonding Using Cu K-Edge X-ray Absorption Spectroscopy.

Copper plays many important roles in ethylene chemistry, thus generating significant interest in understanding the structures, bonding, and properties of copper(I)-ethylene complexes. In this work, the ethylene binding characteristics of a series of isolable Cu(I)-ethylene compounds supported by a systematic set of fluorinated and nonfluorinated bis- and tris(pyrazolyl)borate and the related bis(pyrazolyl)methane ligands have been investigated. Through a combination of X-ray absorption spectroscopy and quantum chemical calculations, we characterize their geometric and electronic structures and the role that fluorinated ligands play in lowering the electron density at Cu sites.

Synthesis and cytotoxicity studies of Cu(I) and Ag(I) complexes based on sterically hindered β-diketonates with different degrees of fluorination.

Design, synthesis, and antitumor properties of Cu(I) and Ag(I) phosphane complexes supported by the anions of sterically hindered β-diketone ligands, 1,3-dimesitylpropane-1,3-dione (HL) and 1,3-bis(3,5-bis(trifluoromethyl)phenyl)-3-hydroxyprop-2-en-1-one (HL) featuring trifluoromethyl or methyl groups on the phenyl moieties have been reported. In order to compare the biological effects of substituents on the phenyl moieties, the analogous copper(I) and silver(I) complexes of the anion of the parent 1,3-diphenylpropane-1,3-dione (HL) ligand were also synthesized and included in the study. In the syntheses of the Cu(I) and Ag(I) complexes, the phosphane coligands triphenylphosphine (PPh) and 1,3,5-triaza-7-phosphaadamantane (PTA) were used to stabilize silver and copper in the +1 oxidation state, preventing the metal ion reduction to Ag(0) or oxidation to Cu(II), respectively.

Copper(I), Silver(I), and Gold(I) Ethylene Complexes of Fluorinated and Boron-Methylated Bis- and Tris(pyridyl)borate Chelators.

Bis- and tris-pyridyl borate ligands containing pyridyl donor arms, a methylated boron cap, and a fluorine-lined coordination pocket have been prepared and utilized in coinage metal chemistry. The tris(pyridyl)borate ligand has been synthesized using a convenient boron source, [NBu][MeBF]. These N-based ligands permitted the isolation of group 11 metal-ethylene complexes [MeB(6-(CF)Py)]M(CH) and [MeB(6-(CF)Py)]M(CH) (M = Cu, Ag, Au).

Remarkably Selective Propylene-Propane Separation Using a Copper Scorpionate.

Propylene is a crucial building block to produce many industrial-scale chemicals including polypropylene. The separation of propylene from propane to reach the high-purity levels needed for downstream applications is a difficult task due to the close similarities in their physical properties. The olefin/paraffin separation including that involving propylene mainly relies on highly energy-intensive distillation processes and accounts for nearly 0.

Isolable acetylene complexes of copper and silver.

Copper and silver play important roles in acetylene transformations but isolable molecules with acetylene bonded to Cu(i) and Ag(i) ions are scarce. This report describes the stabilization of π-acetylene complexes of such metal ions supported by fluorinated and non-fluorinated, pyrazole-based chelators. These Cu(i) and Ag(i) complexes were formed readily in solutions under an atmosphere of excess acetylene and the appropriate ligand supported metal precursor, and could be isolated as crystalline solids, enabling complete characterization using multiple tools including X-ray crystallography.

Bonding situation in isolable silver(I) carbonyl complexes of the Scorpionates.

The bonding situation of Ag(I)CO complexes having a Scorpionate ligand directly attached to the transition metal has been analyzed in detail by means of relativistic density functional theory calculations. To this end, different experimentally characterized complexes together with other representative species have been considered to rationalize the observed shift of the corresponding ν(CO) stretching frequencies and the influence of the substituents in the Scorpionate ligand. With the help of the energy decomposition analysis method combined with the natural orbital for chemical valence it is found that the main contribution to the bonding comes from the electrostatic attractions between the LAg(I) and CO fragments.

Iron pentacarbonyl ligands on silver scorpionates.

Fluorinated tris(pyrazolyl)borate supporting ligands enable the stabilization of silver(I) bonded to a neutral, organometallic Fe(CO) ligand. The Ag-Fe interaction in these molecules is mainly electrostatic in nature, but σ-donor and backbonding contributions between the two metal fragments also play notable roles, which can be modulated by the scorpionate substituents.

Binding Interactions in Copper, Silver and Gold π-Complexes.

The copper(I), silver(I), and gold(I) metals bind π-ligands by σ-bonding and π-back bonding interactions. These interactions were investigated using bidentate ancillary ligands with electron donating and withdrawing substituents. The π-ligands span from ethylene to larger terminal and internal alkenes and alkynes.

Terminal and Internal Alkyne Complexes and Azide-Alkyne Cycloaddition Chemistry of Copper(I) Supported by a Fluorinated Bis(pyrazolyl)borate.

Copper plays an important role in alkyne coordination chemistry and transformations. This report describes the isolation and full characterization of a thermally stable, copper(I) acetylene complex using a highly fluorinated bis(pyrazolyl)borate ligand support. Details of the related copper(I) complex of HC≡CSiMe are also reported.

When SF outplays CF: effects of pentafluorosulfanyl decorated scorpionates on copper.

Polyfluorinated, electron-withdrawing, and sterically demanding supporting ligands are of significant value in chemistry. Here we report the assembly and use of a bis(pyrazolyl)borate, [PhB(3-(SF)Pz)] that combines all such features, and involves underutilized pentafluorosulfanyl substituents. The ethylene and carbonyl chemistry of copper(i) supported by [PhB(3-(SF)Pz)], a comparison to the trifluoromethylated counterparts involving [PhB(3-(CF)Pz)], as well as copper catalyzed cyclopropanation of styrene with ethyl diazoacetate and CFCHN are presented.

A Molecular Compound for Highly Selective Purification of Ethylene.

Purification of C H from an C H /C H mixture is one of the most challenging separation processes, which is achieved mainly through energy-intensive, cryogenic distillation in industry. Sustainable, non-distillation methods are highly desired as alternatives. We discovered that the fluorinated bis(pyrazolyl)borate ligand supported copper(I) complex {[(CF ) Bp]Cu} has features very desirable in an olefin-paraffin separation material.

Synthesis, molecular docking studies, and in vitro antimicrobial evaluation of piperazine and triazolo-pyrazine derivatives.

For this work, two series of new piperazine derivatives (3a-o) and triazolo-pyrazine derivatives (3p-t) were synthesized in a single-step reaction. All twenty adducts were obtained in good to high yields and fully characterized by H NMR, C NMR, IR, and mass spectrometry techniques. To further confirm the chemical identity of the adducts, a crystal of N-{[(4-chlorophenyl)-3-(trifluoromethyl)]-5,6-dihydro-[1,2,4]triazolo[4,3-a]}pyrazine-7(8H)-carboxamide (3t) was prepared and analyzed using X-ray crystallography.

Gold(I) ethylene complexes supported by electron-rich scorpionates.

Ethylene complexes of gold(i) have been stabilized by electron-rich, κ2-bound tris(pyrazolyl)borate ligands. Large up-field shifts of olefinic carbon NMR resonances and relatively long C[double bond, length as m-dash]C distances of gold bound ethylene are indicative of significant Au(i) → ethylene π-backbonding relative to the analog supported by a weakly donating ligand, consistent with the computational data.

Isolable Copper(I) η-Cyclopropene Complexes.

Treatment of bis(pyrazolyl)borate ligand supported [(CF)Bp]Cu(NCMe) with 1,2,3-trisubstituted cyclopropenes produced thermally stable copper(I) η-cyclopropene complexes amenable to detailed solution and solid-state analysis. The [(CF)Bp]Cu(NCMe) also catalyzed [2 + 1]-cycloaddition chemistry of terminal and internal alkynes with ethyl diazoacetate affording cyclopropenes, including those used as ligands in this work. The tris(pyrazolyl)borate [(CF)Tp]Cu(NCMe) is a competent catalyst for this process as well.

New Urea Derivatives as Potential Antimicrobial Agents: Synthesis, Biological Evaluation, and Molecular Docking Studies.

A series of new urea derivatives, containing aryl moieties as potential antimicrobial agents, were designed, synthesized, and characterized by H NMR, C NMR, FT-IR, and LCMS spectral techniques. All newly synthesized compounds were screened in vitro against five bacterial strains ( and ) and two fungal strains ( and ). Variable levels of interaction were observed for these urea derivatives.

Acetylene and terminal alkyne complexes of copper(i) supported by fluorinated pyrazolates: syntheses, structures, and transformations.

Trinuclear {μ-[3,5-(CF)Pz]Cu} reacts with acetylene to produce the 2 : 1 copper(i) acetylene complex, Cu(μ-[3,5-(CF)Pz])(μ-HC[triple bond, length as m-dash]CH). Related Cu(μ-[4-Br-3,5-(CF)Pz])(μ-HC[triple bond, length as m-dash]CH) and Cu(μ-[4-Cl-3,5-(CF)Pz])(μ-HC[triple bond, length as m-dash]CH) have also been isolated using the corresponding copper(i) pyrazolate and acetylene. The 1 : 1 adducts Cu(μ-[3,5-(CF)Pz])(HC[triple bond, length as m-dash]CH) and Cu(μ-[4-Br-3,5-(CF)Pz])(HC[triple bond, length as m-dash]CH) are significantly less stable to the acetylene loss and can be observed in solution at low temperatures under excess acetylene.

Design, synthesis, and molecular docking study of new piperazine derivative as potential antimicrobial agents.

Herein, we describe the successful design and synthesis of seventeen new 1,4-diazinanes, compounds commonly known as piperazines. This group of piperazine derivatives (3a-q) were fully characterized by H NMR, C NMR, FT-IR, and LCMS spectral techniques. The molecular structure of piperazine derivative (3h) was further established by single crystal X-ray diffraction analysis.

Synthesis, molecular docking studies, and antimicrobial evaluation of new structurally diverse ureas.

A series of new urea derivatives (3a-p) have been synthesized from readily available isocyanates and amines in good to high yields. All synthesized compounds were fully characterized using H NMR, C NMR, IR, and mass spectrometry. Additionally, the structure of the compound (3n) was confirmed by single-crystal X-ray diffraction.