1,2-C2B10 can be converted to 1,7-C2B10 by heating to 700°C. It has been suggested that this conversion involves a cubo-octahedron intermediate:

As the cage "flexes" during heating, the dashed bonds shown begin to weaken. (Click on “step 1”).

As the cage continues to flex, these bonds continue to weaken (step 2),.

leading to the cubo-octahedron intermediate (step 3).

Then, new bonds begin to form (step 4),

becoming stronger (step 5),

resulting in the 1,7-carborane (step 6):

To view the conversion in a smooth animation, click on “animate”.

Ortho-carborane conversion




Note! At any time during this process (even in the middle of an animation), the molecule can be rotated by holding down the (left) mouse button and moving the cursor while it is inside the applet frame.