The icosahedral charge-neutral closo-carboranes, 1,2-, 1,7-, and 1,12-  (informally ortho-, meta-, and para-carborane) are particularly stable and are commercially available. The ortho-carborane forms first upon the reaction of decaborane and acetylene. It converts quantitatively to the meta-carborane upon heating in an inert atmosphere. Producing meta-carborane from ortho-carborane requires 700 °C, proceeding in ca. 25% yield.
 is also well established.