Pentacoordinated and hexacoordinated compounds

The chemistry of penta- and hexa-coordinated compounds continues to expand in its breadth and application. In this context, the synthesis, properties and structural investigations on novel cage-phosphoranes, spirophosphoranes, fluorophosphoranes, metallophosphoranes and pentacoordinated corroles have been briefly described. Pentacoordinated phosphoranes have been also postulated as intermediates and transition states in the synthesis of isoquinolines, indolizines,1,3-dienes or furan-monogenes as well as in the carbamate version of the Kabachnik–Field reaction. Furthermore, studies on hexacoordinated phosphorus(v) corroles, carbene-fluorophosphorane adducts and transition metal complexes stabilized by an FAP anion have been reported.