Acceleration of Diels-Alder reactions by mechanical distortion

• 成果类型: Article
• 署名作者: Zholdassov, Yerzhan S.; Yuan, Li; Garcia, Sergio Romero; Kwok, Ryan W.; Boscoboinik, Alejandro; Valles, Daniel J.; Marianski, Mateusz; Martini, Ashlie; Carpick, Robert W.; Braunschweig, Adam B.
• 署名单位: City University of New York (CUNY) System; City University of New York (CUNY) System; Hunter College (CUNY); City University of New York (CUNY) System; University of Pennsylvania; University of California System; University of California Merced
• 刊物名称: SCIENCE
• ISSN/ISSBN: 0036-12312
• DOI: 10.1126/science.adf5273
• 发表日期: 2023-06-08
• 页码: 1053-1058
• 关键词: organic-reactions; activation; FORCE; anthracene; mechanochemistry; pressure; volumes; rates

摘要

Challenges in quantifying how force affects bond formation have hindered the widespread adoption of mechanochemistry. We used parallel tip-based methods to determine reaction rates, activation energies, and activation volumes of force-accelerated [4+2] Diels-Alder cycloadditions between surface-immobilized anthracene and four dienophiles that differ in electronic and steric demand. The rate dependences on pressure were unexpectedly strong, and substantial differences were observed between the dienophiles. Multiscale modeling demonstrated that in proximity to a surface, mechanochemical trajectories ensued that were distinct from those observed solvothermally or under hydrostatic pressure. These results provide a framework for anticipating how experimental geometry, molecular confinement, and directed force contribute to mechanochemical kinetics.