Direct synthesis of dicarbollidesElectronic supplementary information (ESI) available: NMR data and hardcopies of NMR measurements. CCDC 1822659 and 1822660. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c8nj00819a

A direct dicarbon insertion into nine-vertex arachno cages resulting in the formation of C-substituted dicarbollides [7,8-R 2 - nido -7,8-C 2 B 9 H 10 ]− Et 3 NH + via reactions between 4-Et 3 N- arachno -B 9 H 13 and alkynes in refluxing toluene (yields 65-85%) is reported. A substantially new synthesis of dicarbollides based on the dicarbon insertion of alkynes into the nine-vertex 4-Et 3 N- arachno -B 9 H 13 framework is reported.