Facile Pyridine SNAr Reactions via N-Phosphonium-Pyridinium Intermediates

Here we report that N-phosphonium pyridinium intermediates are unusually reactive for pyridine SNAr reactions. Specifically, forming phosphonium salts from halopyridines typically requires elevated temperatures and Lewis acid additives. The alternative activation mode described in this paper permits C-P bond formation to occur at ambient temperatures in many cases, and functions across a broad range of substrates.

Automated summary

The N-phosphonium pyridinium intermediates exhibit unusual reactivity in pyridine SNAr reactions. The activation mode described in this study allows for ambient temperature C-P bond formation and is effective across a wide range of substrates.