This little thing is a monocyclic compound made from 4 carbon atoms and an arsenic atom (as well as 5 hydrogens)…
It bears the unfortunate name of arsole. I’m not even joking. Arsole is also, and I quote, “a mildly aromatic ring”. In fact, there are a whole series of these compounds that exist. That’s right — there are lots of arsoles out there. Technically, a whole family of arsoles.
If you feel the need to read about these arsoles, there are a few papers written about them!
- “Arsole Aromaticity Revisited”
“The aromaticity of arsoles has been debated in the literature for years…”
- “Unusual Substitutions in an Arsole ring”
It actually talks about “carbene insertions”!
- “Studies on the Chemistry of the Arsoles”
G. Markl and H. Hauptmann, J. Organomet. Chem., 248 (1983) 269 (No web link, I’m afraid!)