73050-37-0Relevant articles and documents
Reactions of the phenyl(m-carboran-9-yl)chloronium cation with nucleophiles. Influence of the nature of the onium halogen atom on the reactivity and the reaction pathways of phenyl(m-carboran-9-yl)halonium compounds
Grushin, Vladimir V.,Demkina, Iraida I.,Tolstaya, Tat'yana P.
, p. 1760 - 1765 (2008/10/08)
Reactions of phenyl(m-carboran-9-yl)chloronium tetrafluoroborate (1) with nucleophiles N3-, NO2-, OH-, F-, C5H5N, and PPh3 occur by several pathways, i.e. nucleophilic substitution, one-electron reduction, and degradation of the carborane icosahedron. Comparing reactions of 1 with analogous reactions of phenyl(m-carboran-9-yl)bromonium and phenyl(m-carboran-9-yl)iodonium cations revealed the following pattern. For the sequence [C2B10H11-I-Ph]+, [C2B10H11-Br-Ph]+, [C2B10H11-Cl-Ph]+, degradation of the carborane ligand occurs with increasing ease, one-electron reduction reactions lead to only halogen-phenyl bond cleavage regardless of the halogen atom of the halonium cation, and the regioselectivity of SN reactions decreases dramatically. Nucleophilic substitution in the iodonium cation occurs only at the carborane boron atom. For the bromonium and the chloronium cations, it takes place both at the carborane boron and at the phenyl carbon; however, the regioselectivity of the bromonium cation reaction is significantly higher.
