Bromine isotopes parameters

Recently, Gelman and Halicz presented a new GC-MC-ICP-MS method to study the isotopic composition of bromine species [23]. Instrument parameters were optimized to measure Br and Br simultaneously (Table 17.1), A solution of NIST SRM 987 isotopic reference material was introduced continuously for mass bias correction (via " Sr/ Sr monitoring), and the Kr" signal (Kr is a contaminant in Ar) was used to correct for the contributions of Kr at m/z ratios of 84 and 86. The Br isotopic composition was measured for the following bromine species dibromoethane, 2-bromochlorobenzene, 3-bromotoluene, tribromophenol, and tribromobenzene (listed from the lowest to the highest Br/ Br isotope ratio). 

The oxidation of several monohydric alcohols to the corresponding aldehydes and ketones by bis(quinuclidine)bromine(I) bromide in chloroform and in the presence of pyridinium trifluoroacetate has a two-step mechanism in which transfer of hydride ion from the substrate to the oxidant is rate-determining. The proposed mechanism is supported by the thermodynamic parameters, deuterium kinetic isotope effect, and Hammett reaction constants of the reaction. ... 

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