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o‐Aminoazotoluene (OAT), capable of photoisomerization, and o‐vanillin, a potent comutagen, have been used to synthesize a new ligand, HL, [C6H4(CH3)N=NC6H3(CH3)N=CHC6H3(OH)(OCH3)], which, upon complexation with copper(II), results in a new copper(II) complex‐Cu(L)2, [Cu{C6H4(CH3)N=NC6H3(CH3)N=CHC6H3(OCH3)O}2]. Both HL and Cu(L)2 have been characterized by single‐crystal X‐ray diffraction measurements along with other analytical techniques, for example, IR spectroscopy, NMR spectroscopy, UV–Vis spectroscopy, elemental analysis and mass spectrometry. These compounds were tested with different in vitro anticancer assay as well as with in silico studies. A comparative study has been demonstrated on anticancer activity of HL and Cu(L)2 with the ligand HAZ, {C6H5N=NC6H4N=CHC6H3(OH)(OCH3)} and its Cu‐complex, [Cu(AZ)2, Cu{C6H5N=NC6H4N=CHC6H3(OCH3)O}2]. The sensing properties of HAZ, along with the synthesis and structural properties of both HAZ and Cu(AZ)2, have been reported by our group earlier. Cytotoxicity measurements on MCF7 cell lines show that Cu(L)2 and Cu(AZ)2 have higher anticancer activity than their corresponding ligands. The apoptotic effect of Cu‐complex was studied through nuclear fragmentation assay and AO/EB dual‐staining assay on MCF7 cell line. The IC50 value of Cu(L)2 in 0.01% DMSO/water after 24‐h treatment was found 4.2 μM, which is one of the lowest values with this response time compared to the other analogous anticancer compounds. Finally, we have evaluated the expression of hERα protein with respect to Cu‐complexes, and it was observed that Cu(L)2 caused more down‐regulation of hERα as compared to Cu(AZ)2. [ABSTRACT FROM AUTHOR]

A phenylazo appended ortho‐vanillin Schiff base scaffold (HAZ) has been used for selective colorimetric sensing of Cu2+ in semi‐aqueous medium (methanol–water, 1:1, v/v) in the presence of 16 cations and 20 anions, and the limit of detection is 1.8 × 10−7 M. The structures of HAZ and Cu (II) complex, [Cu(AZ)2], have been characterised by spectroscopic data (UV–Vis, Fourier transform infrared and electron paramagnetic resonance) and established by the single crystal X‐ray diffraction measurement. The Job's plot from the absorption studies has also confirmed the 1:2 stoichiometry of Cu2+:HAZ. The absorption spectrum of [Cu (AZ)2] has returned to the spectrum of HAZ on the addition of Na2EDTA solution which is again recovered upon the addition of Cu2+ solution. Discrete Fourier transform computations were carried out using the coordinates of the X‐ray structures of the compounds, and the molecular functions were used to correlate the solution spectroscopic properties. In addition to this, the probe is treated on MDA‐MB 231 breast cancer cells to check the cytotoxicity. The probe is used for the detection of trace quantity of Cu2+ in the cancer cell. [ABSTRACT FROM AUTHOR]

Template smart inorganic polymers within an organic polymeric matrix to form hybrid nanostructured materials are a unique approach to induce novel multifunctionality. In particular, the fabrication of one‐dimensional materials via electrospinning is an advanced tool, which has gained success in fulfilling the purpose to fabricate two‐dimensional nanostructured materials. We have explored the formation of novel hybrid nanofibers by co‐spinning of poly(ferrocenylphosphinoboranes) Fe A [{Fe(C5H5)(C5H4CH2PHBH2)}n] and Fe B [{Fe(C5H5)(C5H4PHBH2)}n] with poly(ethylene oxide) (PEO) and polystyrene (PS). Fe A and Fe B contain main‐group elements and a ferrocene moiety as pendent group and have different properties compared to their only carbon‐containing counterparts. The use of PEO and polystyrene provided a matrix to spin those inorganic polymers as hybrid nanofibers which were collected in the form of a nonwoven mat. They were characterized by multinuclear NMR spectroscopy, scanning electron microscopy (SEM), and IR spectroscopy. Thermal properties of the polymers have been checked by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). 1H, 31P, and 11B NMR and IR spectroscopy revealed the nature and types of interactions of the components after co‐spinning. The SEM micrographs identify the underlying unidirectional morphology of the generated hybrid nanofibers. Nonetheless, the DSC and TGA confirmed the significant boost toward the thermal stability of the resultant multifunctional fibers. It is believed that these unique types of multifunctional electrospun nanofibers will open new avenues toward the next generation of miniaturized devices. [ABSTRACT FROM AUTHOR]

A systematic approach to obtain bromobismuthates with various bismuth/halide ratios stabilised by 2,6-diisopropylanilinium cations [ArNH3] (Ar = 2,6-diisopropylphenyl) is presented. New bromobismuthate compounds [(ArNH3)(BiBr4)]∞ (1), [(ArNH3)3(Bi2Br9)]∞ (2), [(ArNH3)3(BiBr6)] (3) and [(ArNH3)4(BiBr6)(Br)] (4) with Bi/Br ratios of 1:4, 1:4.5, 1:6 and 1:7 have been isolated and structurally characterised. [Bi2Br9]∞ is a new structural motif in halobismuthate chemistry. In all the compounds, extensive hydrogen bonding is observed between the bromobismuthate moiety and the 2,6-diiosopropylanilinium cation, thus stabilising the inorganic–organic hybrid structures. Preliminary optical spectroscopic studies indicate that the optical band gap can be tuned by controlling the bismuth/halide ratio, which results in different dimensionalities in the halobismuthate structure. The compounds exhibit thermal stability up to 250 °C. [ABSTRACT FROM AUTHOR]

An efficient way to obtain pure diastereomeric mixtures of C-chiral, P-chiral, planar-chiral ferrocenylphosphanes is demonstrated by ortho-lithiation of enantiomerically pure ( SC)- N, N-dimethyl-1-ferrocenylethylamine (Ugi's amine) and reaction with RPX2 [X = Cl, Br; R = tBu, 2,4,6-Me3C6H2 (Mes)]. Four secondary ferrocenylphosphanes [Fe(C5H5)(1-PHR-2-CHR′NMe2-C5H3)] [R′ = H, R = tBu ( 1); R′ = H, R = Mes ( 2); R′ = CH3, R = tBu ( 3); R′ = CH3, R = Mes ( 4)] were synthesised and characterised. Pure diastereomeric mixtures of 1 and 2, a mixture of the pure major diastereomers of 4, as well as diastereomerically pure 3 were obtained by column chromatography under a nitrogen atmosphere. The formation of amine-borane or phosphane-borane adducts was studied by 11B and 31P NMR spectroscopy. A theoretical study was performed to understand the tendency of 1- 4 toward borane adduct formation. [ABSTRACT FROM AUTHOR]

Dehydrocoupling of the ferrocenylphosphine-borane adducts [FcPH2(BH3)] ( 1) [Fc = Fe(C5H5)(C5H4)] and [FcCH2PH2(BH3)] ( 2) with [{Rh(μ-Cl)(cod)}2] (cod = 1,5-cyclooctadiene) as catalyst gave the corresponding phosphorus-boron-based polymers [FcPH(BH2)] n ( 3) and [FcCH2PH(BH2)] n ( 4) as low- (heating in toluene, 3low and 4low) or high-molecular-weight (heating without solvent, 3high or 4high) poly(ferrocenylphosphinoborane)s depending on the reaction conditions. Dehydrocoupling of a racemic mixture of [2- N, N-dimethyl( N-borane)aminomethyl-1-ferrocenyl]phosphine-borane ( 6) resulted in several products, as both BH3 moieties are apparently involved in polymer formation. Quaternization of the amino group in planar-chiral [Fe(C5H5){C5H3(CH2NMe2)PH2}] ( 5) with MeI and treatment of the corresponding ammonium salt [Fe(C5H5){C5H3(CH2NMe3)PH2}]I ( 8) with BH3(THF) gave [Fe(C5H5){C5H3(CH2NMe3)PH2(BH3)}]I ( 9), which proved to be a suitable precursor for selective dehydrocoupling to yield an ionic polymer, namely, {[Fe(C5H5){C5H3(CH2NMe3)PH(BH2)}]I} n. The ferrocenylphosphine-borane adducts 1, 2, and 6 were characterized by 31P, 11B, 1H, and 13C NMR spectroscopy, and the polymers were characterized by multinuclear NMR and IR spectroscopy, gel permeation chromatography (GPC), and thermal analysis [differential thermal analysis (DTA)/thermogravimetry (TG)]. The ionic precursor 9 and the resulting polymer are highly insoluble and were characterized by solid-state 31P NMR spectroscopy, IR spectroscopy, and thermal analysis. Molecular structures of 1, 6, 8, and 9 were determined by X-ray crystallography. [ABSTRACT FROM AUTHOR]

This cover feature shows a diastereomerically pure planar‐chiral secondary ferrocenylphosphane derived from Ugi's amine against a background depicting the Head of Janus, a symbol for the two different features of these compounds: They find application as chiral ligands for metal complexes in asymmetric catalysis, and the corresponding phosphinoborane derivatives could be suitable precursors for the synthesis of chiral P–B polymers by dehydrocoupling. Details are discussed in the article by E. Hey‐Hawkins et al. on page 256 ff (DOI: 10.1002/ejic.201600935). [ABSTRACT FROM AUTHOR]