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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]