Nomenclature cyclopentadienyl complexes

The new compounds described in this paper have a rhenium atom incorporated into closo-l,2-dicarba-3-rhenadodecaborane or c/oro-l-carba-2-rhenadodecaboranc structures. However, to avoid a complicated nomenclature for the complexes reported, and to relate them to the many known rhenium species with 77-co-ordinated cyclopentadienyl ligands, we treat the cages as nido- 1 -vertex ligands with numbering as for an icosahedron from which the twelfth vertex has been removed. 

A special nomenclature for the cyclopentadienyl metal compounds has grown up because of the complexity of their chemical names. The dicyclo-pentadienyl metal compounds, (CsH5)2M, are called ferrocene, cobaltocene, vanadocene, ruthenocene, etc., and these names will be used in this review. Furthermore, the abbreviation Cp will be used to represent C5H5, the cyclopentadienyl radical. 

---