Complete mechanism of benzotriazole synthesis from o-phenylenediamine

Does my suggested mechanism for benzotriazole synthesis look correct? Are the arrows for the cyclization in the right place?


Chemdoodle (which I drew this with) makes the curly arrows look a bit weird.


[![Proposed mechanism of benzotriazole synthesis](https://i.stack.imgur.com/RLfvA.png)](https://i.stack.imgur.com/RLfvA.png)




Species **1** is your seventh structure. The C=N=N atoms are linear and a long reach for the remaining nitrogen. Electrocyclization of **1** to **2** restores aromaticity. Nitrene species **3** allows for a 1,2-shift to an electron-deficient center with concommitant loss of strain in the 4-membered ring to produce 1H-benzo[d][1,2,3]triazole **4**.  
  

Cyclization of **5** $\rightarrow$ **6** and dehydration via **7** gets the job done. Perhaps @Mithoron knows something that I am not aware of.


![](https://i.stack.imgur.com/PJDhZ.jpg)
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