Palladium-catalyzed selective alkoxycarbonylation of different alcohols toward the direct synthesis of cyclobutanecarboxylates

Cycobutanecarboxylates are widely present in bioactive molecules and hold important application value. However, due to the significant strain energy associated with four-membered ring, their direct synthesis poses considerable challenges. Cyclobutanol, a readily synthesized four-membered ring compound, is a direct precursor for synthesizing cyclobutane derivatives. Nonetheless, traditional oxidative esterification between different alcohols leads to the ring-opening of cyclobutanol, resulting in the loss of the cyclobutane motif. Herein, we report a palladium-catalyzed selective alkoxycarbonylation between cyclobutanols and alcohols that directly produces cyclobutanecarboxylates while retaining the cyclobutane framework. This approach demonstrates excellent function group compatibility, enabling the successful conversion of primary, secondary, and tertiary alcohols, and phenols, and delivers the desired esters with outstanding selectivity.