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Enhancing the supercapacitors' performance relies on the increased capacitance and voltage window, which are the current key challenges for developing new materials. In this study, the mononuclear NiII‐bis(oxamato) complex ([nBu4N]2[Ni(opba)], 1) has been synthesized and used as a template in polypyrrole (PPy) based conductive polymer as a novel electrode material for supercapacitor applications. The surface and structural properties of PPy and PPy/1 electrodes were studied using SEM and TEM to elucidate their interactions. The results of characterization techniques revealed that complex 1 altered the morphology, creating a prominent three‐dimensional globular structure in the PPy/1 hybrid material without significant chemical modification. The electrochemical properties of PPy and PPy/1 were investigated by CV, EIS, and GCD analyses. The PPy/1 electrode demonstrated intense pseudocapacitive behavior, showing a significantly widened potential window and increased current compared to the PPy electrode, resulting in enhanced energy storage capacity within the material. This improvement was evaluated by testing a symmetric supercapacitor in a coin cell architecture with an alginate‐based gel acting as both electrolyte and separator. The maximum specific cell capacitance reached 41.6 F g−1 at a current density of 0.2 A g−1, with a remarkable capacity retention of 97 % after 1000 galvanostatic charge/discharge cycles. [ABSTRACT FROM AUTHOR]

The (pentamethylcyclopentadienyl)chloridoiridium(III) complex bearing a κP,κS-bonded Ph2PCH2CH2SPh ligand ([Ir(η5-C5Me5)Cl(Ph2P(CH2)2SPh-κP,κS)]PF6, (1)] was synthesized and characterized. Multinuclear (1H, 13C and 31P) NMR spectroscopy was employed for the determination of the structure. Moreover, SC-XRD confirmed the proposed structure belongs to the "piano stool" type. The Hirshfeld surface analysis outlined the most important intermolecular interactions in the structure. The crystallographic structure was optimized at the B3LYP-D3BJ/6-311++G(d,p)(H,C,P,S,Cl)/LanL2DZ(Ir) level of theory. The applicability of this level was verified through a comparison of experimental and theoretical bond lengths and angles, and 1H and 13C NMR chemical shifts. The Natural Bond Orbital theory was used to identify and quantify the intramolecular stabilization interactions, especially those between donor atoms and Ir(III) ions. Complex 1 was tested on antitumor activity against five human tumor cell lines: MCF-7 breast adenocarcinoma, SW480 colon adenocarcinoma, 518A2 melanoma, 8505C human thyroid carcinoma and A253 submandibular carcinoma. Complex 1 showed superior antitumor activity against cisplatin-resistant MCF-7, SW480 and 8505C cell lines. The mechanism of tumoricidal action on 8505C cells indicates the involvement of caspase-induced apoptosis, accompanied by a considerable reduction in ROS/RNS and proliferation potential of treated cells. [ABSTRACT FROM AUTHOR]

Treatment of unsubstituted and substituted phthalonitrile (1a–d) with appropriate equivalents of sodium methoxide and ammonia afforded the corresponding 1,3-diiminoisoindolines (2a–d), which were converted to cobalt(III)-containing penta-dentate "helmet"-type phthalogens (3a–d) by the reaction with CoCl2·6H2O as templating agent in the inert solvent 1,2,4-trichlorobenzene. The identities of 2a–d and 3a–d were established by elemental analysis, infrared spectroscopy (IR), nuclear magnetic resonance (NMR), and electrospray ionization mass spectrometry (ESI-MS). A computational study was performed to determine the most stable tautomeric form of 2a–c in the gas phase. The solid-state structures of 2b and 2c were determined by single crystal X-ray diffraction (SC-XRD) studies to confirm their existence in the stereoisomeric anti-form, which is aligned with quantum chemical computations. SC-XRD studies of 3a and 3b revealed a slightly distorted octahedral geometry around the CoIII ions which are coordinated by five N-donor atoms and one extra co-ligand, resulting in a coordination environment of CoN5Cl (3a) and CoN5O (3b), respectively. The thermal stabilities of 2a–d and 3a–d were investigated by thermogravimetric analysis (TGA) in the temperature range of 40–500 °C and 40–800 °C, respectively, revealing that 3a–d were converted to the parent cobalt(II)-containing phthalocyanines (4a–d), which was verified independently by furnace heating experiments. Moreover, the electrochemical behavior of 3a was studied exemplarily for the phthalogens by cyclic voltammetry and square wave voltammetry. This study showed that 4a (CoPc) is formed irreversibly by reducing 3a electrochemically. [ABSTRACT FROM AUTHOR]

The synthesis and twin polymerization (TP) of Si(OCH2py)4 (3 a, py=2‐cC5H4N; 3 b, py=3‐cC5H4N; 3 c, py=4‐cC5H4N) is discussed. The solid state structures of 3 b, c were confirmed by single‐crystal X‐ray crystallography showing non‐conventional H‐bonding, forming 2D chains (3 b) or 3D networks (3 c). Thermally induced TP of 3 a–c and their simultaneous polymerization with 2,2'‐spiro‐bi[4H‐1,3,2‐benzodioxasiline] (4) is described. The resulting hybrid materials were characterized by 1H, 13C{1H}, and 29Si{1H} CP MAS NMR spectroscopy confirming the transformation of the SiOCH2 moieties into CH2 groups enabling the formation of the respective polymers. These results were supported by HAADF‐STEM studies, displaying micro‐structuring. Nitrogen‐containing porous carbon materials C_1–C_3 show surface areas of 1300 and 1700 m2 g−1, large pore volumes between 0.6–1.2 cm3 g−1, and nitrogen contents of up to 3.1 at‐%. X‐ray photoemission spectroscopy reveal that pyrrolic, pyridine, and pyridone nitrogen atoms are present. If equimolar amounts of 3 a–c and 4 are simultaneously polymerized in the presence of [Pd(OAc)2] (5), then the Pd nanoparticle‐decorated material Pd@C_3 (900 m2 g−1) was obtained, which showed k values of −0.083 and −0.066 min−1 in the reduction of methylene blue and methyl orange, proving the accessibility of the Pd NPs. [ABSTRACT FROM AUTHOR]

Dinuclear and trinuclear ferrocenylcarboxylato-bridged lanthanide complexes of type [Ln(μO:κ2OO′-O2CFc)(O2CFc)2(H2O)(dmf)]2·(dmf)2 (Ln = Sm (2), Eu (3), Gd (4), Tb (5); Fc = Fe(η5-C5H4)(η5-C5H5)), and novel [Bu4N][Ln3(μ-O2CFc)3(μO:κ2OO′-O2CFc)3(O2CFc)3(μ3-OH)]·[Bu4N]Cl (Ln = Gd (6), Tb (7)) were prepared by the reaction of [LnCl3·6H2O] (synthesis of 2–5) or LnCl3 (synthesis of 6, 7) with FcCO2H (1) in the ratio of 1 : 3. As evidenced by single crystal X-ray structure determination, in 2–5 the lanthanide ions are connected by symmetric FcCO2 units. In addition, two ferrocenylcarboxylato groups are μ-bridged to LnIII. Each LnIII ion is coordinated by nine oxygen donor atoms derived from one H2O, one dmf and three carboxylates. The latter are found in chelating κ2 and bridging μ,κ3 coordination modes. Complexes 6 and 7 assemble three LnIII cores around a central μ3-netting hydroxide and nine FcCO2 entities. A combination of κ2, μ,κ2 and μ,κ3 coordination modes results in an eight-fold coordination sphere for each metal, which is best described as bicapped trigonal prismatic. IR spectroscopy confirms the chelating and bridging motifs. Electrochemical studies of complexes 2–7via cyclic voltammetry (CV) and square-wave voltammetry (SWV) showed one redox event between E°′ = 250 and 260 mV vs. FcH/FcH+ for 2–5 with all six FcCO2 redox events superimposed. Complexes 6 and 7 show a total of three events in the CV with the oxidations of the nine FcCO2 units occurring in close proximity. Deconvolution of individual redox events correlates well with the mononuclear complex [Bu4N][Gd(O2CFc)4]. UV–Vis/NIR spectroelectrochemical measurements of 7 did not reveal electron transfer between either Fc units, nor the coordinated lanthanides and resembled the absorption behavior of [Bu4N][Tb(O2CFc)4]. DFT (Density Functional Theory) calculations on the B3LYP def2-TZVP level of theory were carried out to assign the order of redox events in 6 showing that the spatial distance towards the most recent redox center, instead of the binding mode, is decisive. [ABSTRACT FROM AUTHOR]

Purification via flash column chromatography (silica gel; 1.5 × 18 cm, cyclohexane/EtOAc = 10:1, 6 mL, #32-58) afforded homoannulene ester B 7d b (12.0 mg, 37.9 mol, 60%) as an orange oil; I R SB f sb i = 0.32 (silica gel, cyclohexane/EtOAc = 8:2). Keywords: homoaromaticity; aromaticity; hydrocarbons; synthesis; HOMA; bond lengths EN homoaromaticity aromaticity hydrocarbons synthesis HOMA bond lengths 2658 2669 12 08/17/23 20230901 NES 230901 Graph Molecules that bear an interrupted cyclic conjugated system, but nevertheless exhibit characteristics of an aromatic compound are termed homoaromatic. Purification via flash column chromatography (silica gel; 3 × 13 cm, cyclohexane/EtOAc = 9:1, #12-16, 20 mL) afforded acetoacetate B 10c b (460 mg, 1.70 mmol, 64%) as a slightly pink oil; I R SB f sb i = 0.34 (silica gel, cyclohexane/EtOAc = 8:2). Purification via flash column chromatography (silica gel; 3 × 20 cm, cyclohexane/EtOAc = 9:1, 20 mL, #18-21) afforded acetoacetate B 10d b (130 mg, 406 mol, 38%) as a colorless oil; I R SB f sb i = 0.34 (silica gel, cyclohexane/EtOAc = 8:2). [Extracted from the article]