Xanthate complexes adducts

Pyridazine forms a stable adduct with iodine, with semiconductor properties. " Similar complexes were prepared from iodine mono-ehloride, bromine, and nickel(II) ethyl xanthate. Complexes of pyrida-zines with iron carbonyls and with iron carbonyls and triphenylphosphine have been prepared and investigated. " Complexes of pyridazines with boron trihalides, silver salts, mercury(I) salts, iridium salts, " ruthenium salts, and chromium carbonyls are re-... 

Of the transition metals, the nickel triad has been the most studied in terms of xanthate structures, especially nickel xanthates. Thus, binary xanthate structures are known for all elements with no less than 15 binary nickel xanthate structures known and these aggregate in the solid state in six distinct supramolecular architectures. There is also a rich diversity of adducts as well as mixed-ligand complexes, in particular for nickel. 

Alkenyl boronic esters can also be used to trap nucleophilic carbon-centered radicals, which can be generated by the tin hydride method or by decomposition of an organomercurial derivative. The influence of the olefin and boron substituents on the reactivity and regioselectivity has been determined. Vinyl-9-BBN displayed significantly better reactivity than the boronic ester while the directing effect of the boronic ester group is weaker than that of an ester function. The Barton radical chain procedure furnished very stable adducts due to an intramolecular complexation between boron and nitrogen (Scheme 9.12) [29]. Radical additions of various xanthates also occurred smoothly in the presence of lauroyl peroxide [30]. Intermolecular ver-... 

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