Quantitative syntheses of permethylated closo -1,10-R 2 C 2 B 8 Me 8 (R = H, Me) carboranes. Egg-shaped hydrocarbons on the Frontier between inorganic and organic chemistry.

Electrophilic methylation of the closo -1,10-R 2 C 2 B 8 H 8 (1) (R = H or Me) dicarbaboranes at higher temperatures or thermal rearrangement of the 1,6-R 2 C 2 B 8 Me 8 (3) compounds at 400-500 °C generated the B-permethylated derivatives closo -1,10-R 2 C 2 B 8 Me 8 (2) in quantitative (>95%) yields. The compounds exhibit extreme air stability as a consequence of a rigid, egg shaped hydrocarbon structures incorporating inner 1,10-C 2 B 8 carborane core.