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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]