Arynes Bergman cyclization

An interesting route to 98 was suggested by Cramer et al. " cyclization of isonitrile 110 could lead to 98 in a rearrangement analogous to the Bergman cyclization. The activation enthalpy for the only slightly exothermic reaction was estimated at 18 kcal/mol. However, this novel access to m-arynes could not be realized experimentally so far. 

Cramer, C. J. 1998. Bergman, Aza-Bergman, and Protonated Aza-Bergman Cyclizations and Intermediate 2,5-Arynes Chemistry and Challenges to Computation. 1. Am. Chem. Soc.. 120. 6261. 

Cramer, C. J. Bergman, aza-Bergman, and protonated aza-Bergman cyclizations and intermediate 2,5-arynes chemistry and challenges to computation, J. Am. Chem. Soc. 1998,120, 6261-6269. 

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