Cyclic oxonium derivatives of cobalt and iron bis(dicarbollides) and their use in organic synthesis

The rapid progress in the chemistry of carboranes and other polyhedral boron compounds makes the development of methods for the synthesis of their various functional derivatives a high priority. The formation of cyclic oxonium derivatives followed by the ring opening is one of the most efficient methods for the preparation of these compounds. This review addresses the data on the use of the nucleophilic ring opening of cyclic oxonium derivatives based on cobalt and iron bis(dicarbollides), which have been extensively studied in recent years. Reactions involving O-, N-, S-, P- and C-nucleophiles are considered as a route to the targeted synthesis of a wide range of organic boron derivatives, in particular various boron-containing biologically active compounds. Possible applications of the reaction products are discussed.