Halogens, detection replacement

There are reasons to explain the catalytic activity of copper(ll) in terms of cation-radical mechanism. This mechanism is confirmed by the unusual direction of Meerwein reaction in some cases, for example, when the replacement of halogen by an aryl radical occurs in the reaction of halo-styrenes with aryldiazonium salts (Obushak et al. 1991). A cation-radical in the system [olefin-Cu(II)] has been detected by UV spectroscopy (Obushak et al. 1991). In the cases of cis isomers of benzylidenacetone (Allard and Levisalles 1972) and maleic esters (Isaev et al. 1972), the unreacted... 

Other investigators used flame emission as a modified Beilstein test for the detection of halogenated hydrocarbons. In such an arrangement, a green flame was produced when halogenated hydrocarbons were burned in the presence of a copper wire. Replacement of the copper with indium improves specificity and... 

The detection of gas phase halogens by He MIP-MS has also been investigated by Brown and co-workers [98]. They utilized a commercially available ICP-MS instrument. The ICP torch box was removed and replaced with an internally tuned TMqio microwave cavity. The He plasma was formed using a demountable tangential flow torch. This was used in an effort to create a central region in the plasma, rich in analyte ions which allows for maximum sensitivity when sampling the plasma with the mass spectrometer. 

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