Alpha‐Ester Aryl Diazirines: Low‐Temperature Carbene Progenitors for Materials Applications

Trifluoromethyl aryl diazirines are ubiquitous in chemical biology applications, and are increasingly used in materials science. While the electron‐withdrawing α ‐CF 3 group is known to stabilize the carbene resulting from diazirine activation, no alternative electron‐withdrawing groups have been systematically studied. Here, we describe the synthesis of the first α ‐ester aryl diazirines and show that they activate at lower temperatures than their trifluoromethyl‐containing analogs, while still permitting tunable activation and good efficiency in CH insertion reactions. We anticipate the use of α ‐ester aryl diazirines in materials science applications (due to their high insertion yield with a nonfunctionalized aliphatic model substrate) and biological wound healing (due to their ability to be thermally activated at < 37°C).