# meta-Diethynylbenzene dianion

(Redirected from Meta-diethynylbenzene dianion)
Names Properties Meta-diethynylbenzene dianion The compound C6H4(C3HO2)2 used for the synthesis of Meta-diethynylbenzene dianion IUPAC name Meta-diethynylbenzene dianion Chemical formula C6H4C2−4 Main hazards Extremely corrosive Related bases Ortho-diethynylbenzene dianion Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). verify (what is  ?) Infobox references

The meta-diethynylbenzene dianion is a structural isomer of the ortho-diethynylbenzene dianion. The meta-diethynylbenzene dianion is not as strong as ortho-diethynylbenzene dianion, but it is still the second-strongest superbase. Like the ortho-diethynylbenzene dianion, the meta-diethynylbenzene dianion exists in the gas state, contrary to the other bases and superbases which exist in the solution state. In the meta-diethynylbenzene dianion, the two negatively charged ethynyl (−C
2
H
2
) groups are bonded to the first and third carbon atoms of the benzene ring. But in the ortho-diethynylbenzene dianion, the ethynyl groups are bonded to the first and second carbon atoms of the benzene ring. Like Ortho-diethynylbenzene dianion, Meta-diethynylbenzene dianion has no known use.

## Synthesis

Step 1
A sample of meta-C6H4(C3HO2)2 is taken.
Step 2
In this next step, the parent compound is subjected through electrospray ionization (ESI) and consequently, loses two Hydrogen atoms and therefore, acquires a charge of −2. The new compound's chemical formula is [C6H4(C3O2)2]2−
Step 3
The ionized parent compound [C6H4(C3O2)2]2− is subjected to collision-induced dissociation (CID), because of which, one of the carboxylate anion loses a Carbon dioxide molecule to become [C6H4(C5O2)]2−.
Step 4
The meta-[C6H4(C3O2)2]2− compound is again subjected to collision-induced dissociation, because of which, the other carboxylate anion loses the other Carbon dioxide molecule and becomes meta-[C6H4(C5O2)]2−
Step 5
Therefore, the meta-diethynylbenzene dianion [C6H4(C2)2]2− is formed, having lost, in total, two hydrogen atoms and two molecules of carbon dioxide.

The same process can generate either ortho-diethynylbenzene dianion and Meta-diethynylbenzene dianion depending on which isomer of the original compound is used.

### Summary

${\displaystyle {\ce {\overset {}{C6H4(C3HO2)2->[{\ce {ESI}}][][C6H4(C3O2)2]^{2-}->[{\ce {CID}}][][C6H4(C5O2)]^{2-}->[{\ce {CID}}][][C6H4(C2)2]^{2-}}}}}$