Is phosphorine (C₅H₅P) aromatic?

Phophorine seems aromatic as it has 6 conjugated electrons. But the answer given is that it is not. This seems odd since pyridine has a similar structure and is also aromatic. Thus I ask is phospohrine aromatic or not?


[![enter image description here](https://i.stack.imgur.com/wnN1qb.png)](https://i.stack.imgur.com/wnN1qb.png)




[Phosphorine](https://en.wikipedia.org/wiki/Phosphorine) (IUPAC: phosphinine) actually has aromatic character nearly as great (88%) as that of benzene. According to the reference, phosphorine is sufficiently stable to be handled without air-free techniques; and it undergoes electrophilic substitution reactions similar to those of benzene.


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