/sci/ - Science & Math

asked this question in another thread - got no valid reply besides ferrocen which i knew about before. My picture somewhat implies there is a carbon exactly in the ring though thats not neccessarily what i mean.

Can u have a bond (or even an atom (for example carbon like in the picture) in a benzene ring? If not, whats the smallest ring/pi-system/whatever that can have this ?

Is there a way to have a bond (or double or whatever) to go through benzene ring?
If not whats the smallest size ring that can have bondings go right through the middle? no fucking clue how to google that

pic related