A Practical Approach to Cyclopropanation of Masked <i>o</i>‐Benzoquinones with Applications in Tropolone Derivative Synthesis

Abstract The Corey–Chaykovsky cyclopropanation of readily available masked o ‐benzoquinones (MOBs) has been investigated to generate functionalized bicyclo[4.1.0]heptane derivatives with regioselectivity. The resulting bicyclic products were subjected to a sequence of hydrolysis, BF₃ ⋅ Et₂O‐mediated ring‐opening, and then again hydrolysis to access various tropolone derivatives – a class of molecules with significant roles in synthetic, biological, and theoretical chemistry. Utilizing an improved approach based on established cyclopropanation and ring‐opening strategies, several bicyclo[4.1.0]heptanes, tropolone difluorides, and tropolones can be synthesized from readily available MOBs. Our efforts focused on modifying each step to make these reactions general and of considerable practical value.