A General Synthetic Strategy toward the Truxillate Natural Products via Solid-State Photocycloadditions
Ellie F. Plachinski, Hyung Joo Kim, Matthew J. Genzink, Kyana M. Sanders, Riley M. Kelch, Ilia A. Guzei, Tehshik P. Yoon
Abstract
The truxillates constitute a large class of dimeric natural products featuring a central, highly substituted cyclobutane core. In principle, these structures could be efficiently synthesized via [2 + 2] photocycloaddition. However, the difficulty in controlling the high-energy electronically excited reactive intermediates in the solution state can lead to poor regio- and diastereocontrol. This has limited the use of photocycloaddition methodology toward the synthesis of this important class of natural products. Herein, we demonstrate that acid-controlled precipitation of C -acyl imidazoles promotes a highly selective solid-state photocycloaddition, and the products of this reaction can be quickly transformed into truxillate natural products.