The idea of coordinating biologically active ligand systems to metal centers to exploit their synergistic effects has gained momentum. Therefore, in this report, three Ru complexes - of morpholine-derived thiosemicarbazone ligands have been prepared and characterized by spectroscopy and HRMS along with the structure of through a single-crystal X-ray diffraction study. The solution stability of - was tested using conventional techniques such as UV-vis and HRMS.
View Article and Find Full Text PDFThree stable oxidovanadium(IV) [VOL] complexes (1-3) were synthesized through the incorporation of unsymmetrical salen ligands (HL). All the ligands are synthesized, and their vanadium compounds were thoroughly characterized by CHNS analysis, various spectroscopy methods (IR, UV-Vis, NMR spectroscopy), and HR-ESI-MS. The structures of 1-3 were validated through the single-crystal X-ray analysis.
View Article and Find Full Text PDFWe report the use of porous organic layers in two-dimensional hybrid organic-inorganic perovskites (HOIPs) to facilitate permanent small molecule intercalation and new post-synthetic modifications. While HOIPs are well-studied for a variety of optoelectronic applications, the ability to manipulate their structure after synthesis is another handle for control of physical properties and could even enable use in future applications. If designed properly, a porous interlayer could facilitate these post-synthetic transformations.
View Article and Find Full Text PDFThis study investigates the electronic interactions and charge redistribution at the dopant-support interface using a Cu/CoSe cluster construct. Specifically, the redox cluster series [CuCoSeL] ([-Cu]; = 0, -1, -2, -3; L = PhPNTol, Ph = phenyl, Tol = -tolyl) spanning four distinct oxidation states is synthesized and characterized using a multitude of techniques, including multinuclear NMR, UV-vis, XANES, and X-ray crystallography. Structural investigations indicate that the clusters are isostructural and chiral, adopting a pseudo- symmetry.
View Article and Find Full Text PDFConverting triplet dioxygen into a powerful oxidant is fundamentally important to life. The study reported herein quantitatively examines the formation of a well-characterized, reactive, O-derived thiolate ligated Fe-superoxo using low-temperature stopped-flow kinetics. Comparison of the kinetic barriers to the formation of this species two routes, involving either the addition of (a) O to [Fe(S N(Pr,Pr))] (1) or (b) superoxide to [Fe(S N(Pr,Pr))] (3) is shown to provide insight into the mechanism of O activation.
View Article and Find Full Text PDFDirecting groups guide substitution patterns in organic synthetic schemes, but little is known about pathways to control reactivity patterns, such as regioselectivity, in complex inorganic systems such as bioinorganic cofactors or extended surfaces. Interadsorbate effects are known to encode surface reactivity patterns in inorganic materials, modulating the location and binding strength of ligands. However, owing to limited experimental resolution into complex inorganic structures, there is little opportunity to resolve these effects on the atomic scale.
View Article and Find Full Text PDFThe synthesis of novel metal-organic coordination polymers (MOCP) with the chemical formula [MnL (SCN)(OH)]·CHOH [L = 1,5-bis(pyridine-4-ylmethylene) carbonohydrazide] {} was accomplished using two different techniques: solvothermal and sonochemical ultrasonic-assisted. An investigation was carried out to examine the impact of various factors such as reaction time, sonication power, temperature, and reactant concentration on the morphology and size of the crystals. Interestingly, it was found that sonication power and temperature did not affect the crystals' morphology and size.
View Article and Find Full Text PDFThe discovery of magic-sized clusters as intermediates in the synthesis of colloidal quantum dots has allowed for insight into formation pathways and provided atomically precise molecular platforms for studying the structure and surface chemistry of those materials. The synthesis of monodisperse InAs quantum dots has been developed through the use of indium carboxylate and As(SiMe) as precursors and documented to proceed through the formation of magic-sized intermediates. Herein, we report the synthesis, isolation, and single-crystal X-ray diffraction structure of an InAs nanocluster that is ubiquitous across reports of InAs quantum dot synthesis.
View Article and Find Full Text PDFAllylsilanes can be regioselectively transformed into the corresponding 3-silylfluorohydrin in good yield using a sequence of epoxidation followed by treatment with HF·EtN with or without isolation of the intermediate epoxide. Various silicon-substitutions are tolerated, resulting in a range of 2-fluoro-3-silylpropan-1-ol products from this method. Whereas other fluorohydrin syntheses by epoxide opening using HF·EtN generally require more forcing conditions (e.
View Article and Find Full Text PDFIndium phosphide quantum dots have become an industrially relevant material for solid-state lighting and wide color gamut displays. The synthesis of indium phosphide quantum dots from indium carboxylates and tris(trimethylsilyl)phosphine (P(SiMe)) is understood to proceed through the formation of magic-sized clusters, with InP(OCR) being the key isolable intermediate. The reactivity of the InP(OCR) cluster is a vital parameter in controlling the conversion to quantum dots.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
November 2023
Due to their unique topology and distinct physical properties, cycloparaphenylenes (CPPs) are attractive building blocks for new materials synthesis. While both noncovalent interactions and irreversible covalent bonds have been used to link CPP monomers into extended materials, a coordination chemistry approach remains less explored. Here we show that nucleophilic aromatic substitution reactions can be leveraged to rapidly introduce donor groups (-OR, -SR) onto polyfluorinated CPP rings.
View Article and Find Full Text PDFThis study provides insights into the electronic structure of an atomically precise Fe/CoSe cluster and the extent of redox cooperativity between the Fe active site and the noninnocent CoSe support. Chemical oxidation studies enable the isolation of two types of oxidized Fe/CoSe clusters, in which the nature of the counterion (I or OTf) significantly impacts the structural interactions between Fe and the CoSe unit. Experimental characterization by single crystal X-ray diffraction, Fe Mössbauer spectroscopy, and P{H} NMR spectroscopy is complemented by computational analysis.
View Article and Find Full Text PDFFour new oxidovanadium [VOL(ema)] complexes (-) have been synthesized using tridentate binegative ONO donor ligands HL [HL: ()--(2-hydroxybenzylidene)furan-2-carbohydrazide; HL: ()--(4-(diethylamino)-2-hydroxybenzylidene)thiophene-2-carbohydrazide; HL: ()-2-(4-(diethylamino)-2-hydroxybenzylideneamino)-4-methylphenol; HL: ()-2-(3-ethoxy-2-hydroxybenzylideneamino)-4-methylphenol] and ethyl maltol (Hema) as a bidentate uninegative coligand and characterized by CHNS analysis, IR, UV-vis, NMR, and HR-ESI-MS methods. The structures of , , and are confirmed by single-crystal X-ray analysis. The hydrophobicity and hydrolytic stability of the complexes are tested using NMR and HR-ESI-MS and correlated with their observed biological activities.
View Article and Find Full Text PDFRedox-active tetraoxolene ligands such as 1,4-dihydroxybenzoquinone provide access to a diversity of metal-organic architectures, many of which display interesting magnetic behavior and high electrical conductivity. Here, we take a closer look at how structure dictates physical properties in a series of 1D iron-tetraoxolene chains. Using a diphenyl-derivatized tetraoxolene ligand (HPhdhbq), we show that the steric profile of the coordinating solvent controls whether linear or helical chains are exclusively formed.
View Article and Find Full Text PDFActa Crystallogr E Crystallogr Commun
March 2023
The structures of ()-butan-2-yl -(4-nitro-phen-yl)thio-carbamate, CHNOS, (I), ()-butan-2-yl -(4-meth-oxy-phen-yl)thio-carbamate, CHNOS, (II), ()-butan-2-yl -(4-fluoro-phen-yl)thio-carbamate, CHFNOS, (III), and ()-butan-2-yl -(4-chloro-phen-yl)thio-carbamate, CHClNOS, (IV), all at 100 K, have monoclinic (2) symmetry with two independent mol-ecules in the asymmetric unit. The Flack absolute structure parameters in all cases confirm the absence of inversion symmetry. The structures display N-H⋯S hydrogen bonds, resulting in (8) hydrogen-bonded ring synthons connecting the two independent mol-ecules.
View Article and Find Full Text PDFJ Inorg Biochem
January 2023
A series of nine new complexes of ruthenium(II), rhodium(III), and iridium(III) incorporated with pyrazoline-based ligands were synthesized and characterized by various spectroscopic techniques such as FTIR, H NMR, C NMR, UV-Vis spectroscopy, ESI-MS spectrometry and X-ray crystallographic studies. All the synthesized compounds were assessed for their antibacterial abilities against Gram-positive and Gram-negative bacterial strains. The compounds showed better antibacterial activity against two Gram-positive bacteria (Staphylococcus aureus and Bacillus Thuringiensis), with activities superior to standard kanamycin.
View Article and Find Full Text PDFThis study provides atomistic insights into the interface between a single-site catalyst and a transition metal chalcogenide support and reveals that peak catalytic activity occurs when edge/support redox cooperativity is maximized. A molecular platform MCoSe(PEt)(L) (-M, M = Cr, Mn, Fe, Co, Cu, and Zn) was designed in which the active site (M)/support (CoSe) interactions are interrogated by systematically probing the electronic and structural changes that occur as the identity of the metal varies. All 3d transition metal -M clusters display remarkable catalytic activity for coupling tosyl azide and -butyl isocyanide, with Mn and Co derivatives showing the fastest turnover in the series.
View Article and Find Full Text PDFA record power conversion efficiency (PCE) of over 19% is realized in planar-mixed heterojunction (PMHJ) organic solar cells (OSCs) by adopting the asymmetric selenium substitution strategy in making a pseudosymmetric electron acceptor, BS3TSe-4F. The combined molecular asymmetry with more polarizable selenium substitution increases the dielectric constant of the D18/BS3TSe-4F blend, helping lower the exciton binding energy. On the other hand, dimer packing in BS3TSe-4F is facilitated to enable free charge generation, helping more efficient exciton dissociation and lowering the radiative recombination loss (ΔE ) of OSCs.
View Article and Find Full Text PDFThis study uncovers the interconnected reactivity of the three catalytically active sites of an atomically precise nanocluster Cr(py)CoSeL ((py), L = PhPNTol, Ph = phenyl, Tol = 4-tolyl). Catalytic and stoichiometric studies into tosyl azide activation and carbodiimide formation enabled the isolation and crystallographic characterization of key catalytically competent metal-imido intermediates, including the tris(imido) cluster (NTs), the catalytic resting state (NTs)(CNBu), and the site-differentiated mono(imido) cluster (NTs)(CNBu). In the stoichiometric regime, nitrene transfer proceeds via a stepwise mechanism, with the three active sites engaging sequentially to produce carbodiimide.
View Article and Find Full Text PDFIn this work, one oxidomethoxidovanadium(V) [VO(L)(OMe)] (1) and two mixed-ligand oxidovanadium(IV) [VO(L)(phen)] (2), and [VO(L)(bipy)] (3) complexes have been synthesized using a tridentate bi-negative ONS donor dithiocarbazate as main ligand, HL [where, HL = S-benzyl-3-(2-hydroxy-3-ethoxyphenyl)methylenedithiocarbazate] along with 1,10-phenanthroline (phen) (for 2) and 2,2'-bipyridine (bipy) (for 3) as co-ligands. The ligand and complexes have been characterised by FT-IR, UV-vis, NMR, and HR-ESI-MS techniques. Distorted square pyramidal for 1, and distorted octahedral geometry for 2 and 3 was confirmed by single crystal X-ray crystallography.
View Article and Find Full Text PDFWe demonstrate that allosteric effects and redox state changes can be harnessed to create a switch that selectively and reversibly regulates the coordination chemistry of a single site on the surface of a molecular cluster. This redox-switchable allostery is employed as a guiding force to assemble the molecular clusters ZnCoSeL' (L' = PhPN(H)Tol, Ph = phenyl, Tol = 4-tolyl) into materials of predetermined dimensionality (1- or 2-D) and to encode them with emissive properties. This work paves the path to program the assembly and function of inorganic clusters into stimuli-responsive, atomically precise materials.
View Article and Find Full Text PDFThe multiredox reactivity of bioinorganic cofactors is often coupled to proton transfers. Here we investigate the structural, thermochemical, and electronic structure of ruthenium-amino/amido complexes with multi- proton-coupled electron transfer reactivity. The bis(amino)ruthenium(II) and bis(amido)ruthenium(IV) complexes [Ru(bpy)(en*)] ( ) and [Ru(bpy)(en*-H)] ( ) interconvert reversibly with the transfer of 2e/2H (bpy = 2,2'-bipyridine, en* = 2,3-diamino-2,3-dimethylbutane).
View Article and Find Full Text PDFThe rapid development of non-fullerene acceptors (NFAs) with strong near-infrared absorption has led to remarkably enhanced short-circuit current density () values in organic solar cells (OSCs). NFAs based on the benzotriazole (Bz) fused-ring π-core have great potential in delivering both high and decent open-circuit voltage values due to their strong intramolecular charge transfer with reasonably low energy loss. In this work, we have designed and synthesized a series of Bz-based NFAs, PN6SBO-4F, AN6SBO-4F and EHN6SEH-4F, regiospecific -alkyl engineering based on the high-performance NFA mBzS-4F that was reported previously.
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