Mechanism-Based Alternative Benzannulation

In several cases, investigators have invented novel benzannulation reactions based on a consideration of the mechanism for the Dotz reaction. In these investigations, alternative routes to specific intermediates in the mechanism proposed for the reaction were developed. Once formed, these compounds then enter readily into the benzannulation reaction pathway. 

CO-insertion reaction was considerably less efficient, due to the electron-rich nature of the carbene complex. 

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