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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]

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]

Transition-metal-catalyzed dehydrocoupling of tert-butylferrocenylphosphine-borane (2) with [{Rh(μ-Cl)(1,5-cod)}2] (cod = cyclooctadiene) as the catalyst gave the homocoupled product [Fc(tBu)(H)P(BH2)P(Fc)(tBu)(BH2X)] [3; Fc = Fe(C5H5)(C5H4), X = H/Cl], while cross-dehydrocoupling with the tertiary phosphine-boranes P(tBu)(nBu)2(BH3) (2a) and PPh(nBu)2(BH3) (2b) using [Rh(1,5-cod)2]OTf (OTf = trifluoromethanesulfonate) gave the first cross-dehydrocoupled products reported to date, [Fc(tBu)(BH3)P(BH2)P(tBu)(nBu)2] (4) and [Fc(tBu)(BH3)P(BH2)PPh(nBu)2] (5), in moderate yields. Compounds 2-5 were characterized by NMR spectroscopy (¹H, 13C, 31P, and 11B), IR spectroscopy, mass spectrometry, and single-crystal X-ray structure determination. [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]

We report here, the first example of an inorganic–organic hybrid material incorporating a helical iodobismuthate [BiI4]∞ templated by 2,6-diisopropylanilinium cations. The realisation of the helical iodobismuthate opens up the possibility of a wide range of physical properties among hybrid materials. [ABSTRACT FROM AUTHOR]

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]

• Main group compounds. • Inorganic-organic hybrid materials. • Nitrate inserted halobismuthates. • Mixed halobismuthates. Two binuclear halobismuthates (Bi 2 X 10)4− (X = Cl (1) and Br (2)) containing m -phenylenediammonium cation m PDA-(H) 2 2+ or m PDA-(H)]1+ starting from corresponding BiX 3 (X = Cl, Br) and their nitrate derivatives i.e., [Bi 2 X 8 (NO 3) 2 m PDA-(H) 2 2 (X = Cl (3) and Br (4)) starting from Bi(NO 3) 3 ,5H 2 O have been synthesized. 3 and 4 are the first examples of mixed halobismuthates where nitrate ions are coordinated to bismuth centers along with other halide ions. All the compounds have been characterized by single crystal XRD, elemental analysis and IR spectroscopy. The structural comparisons of 1 – 4 have been discussed. [ABSTRACT FROM AUTHOR]

Synthesis of iodobismuthates and tuning their properties attracted a lots of attention due to their contribution in developing opto-electronic devices. Two 1-D polymeric iodobismuthate compounds, {[2,6-(NH 2) 2 PyH][BiI 4 ]} n (1), {[4-NMe 2 PyH][BiI 4 ]} n (2), [Py: Pyridine] have been reported, where structurally similar polymeric anionic iodobismuthate is stabilised by two different pyridinium cations namely 2,6-bis(amino)pyridine and 4-(N , N -dimethylamino)pyridine derivatives. The compounds have been characterised by single crystal XRD, IR and elemental analysis. It is interesting to observe that the structurally similar compounds differ drastically in their optical properties because of slight variation in the cations. Comparison in structural features and their thermal, optical properties (band gap: 1.91 eV (1); 2.10 eV (2)) have been discussed. Thermochromism is exhibited by 1. DFT studies of compound 1 has been performed considering the crystal structure measured at two different temperature and the role of cation in tuning the optical properties of iodobismuthates has been established. [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]

Dicarba- closo-dodecaboranes(12) (C2B10H12, carbaboranes) are highly hydrophobic and stable icosahedral carbon-containing boron clusters. The cage framework of these clusters can be modified with a variety of substituents, both at the carbon and at the boron atoms. Substituted carbaboranes are of interest in medicine as boron neutron capture therapy (BNCT) agents or as pharmacophores. High and selective accumulation in tumour cells is an important requirement for a BNCT agent and is achieved by incorporating boron-rich, water-soluble carbaborane derivatives into breast tumour-selective modified neuropeptide Y, [F7, P34]-NPY. Preliminary studies showed that the receptor binding affinity and signal transduction of the boron-modified peptides were very well retained. Use of carbaboranes as pharmacophores was shown by replacement of Bpa32 (Bpa=benzoylphenylalanine) in the reduced-size NPY analogue [Pro30, Nle31, Bpa32, Leu34]-NPY 28-36 by ortho-carbaboranyl propanoic acid. The inclusion of the carbaborane derivative resulted in a short NPY agonist with an interesting hY2R/hY4R preference. This might be a promising approach in the field of anti-obesity drug development. [ABSTRACT FROM AUTHOR]