Pujol Mireia, Bru Gerard, Mazuryk Taras, Tarasewicz Anika, Carbó Jorge J, Méndez María, Fernández Elena
Faculty of Chemistry, University Rovira i Virgili, 43007 Tarragona, Spain.
Integrated Drug Discovery, Industriepark Höchst, Sanofi R&D, Bldg. G838, 65926 Frankfurt am Main, Germany.
ACS Catal. 2025 Jul 1;15(14):12063-12074. doi: 10.1021/acscatal.5c02260. eCollection 2025 Jul 18.
Chemoselective borylcupration of borylated ()-skipped dienoates is controlled by the ester group to access 3,3-di-(pinacol)-borylalkenoates. Electrophilic trapping with H, D, alkyl-, benzyl-, or allyl halides, as well as isocyanates has proved to be efficient for α-functionalized products. The Cu-catalyzed borylcupration of skipped dienoates containing C-Br bonds resulted in concomitant ring closing sequences toward alkylidene -diborylcyclobutane scaffolds. We performed DFT calculations to characterize the reaction mechanism of the formation of -diborylcyclobutanes. The key steps of the proposal comprise a selective borylcupration directed by alkene substituents, followed by an intramolecular C-C coupling toward strained four-membered rings assisted by the potassium cation. We also analyzed the effect of the nature of the halogen leaving group on the selectivity. The versatility of alkylidene cyclobutanes has been demonstrated through postfunctionalization reactions.
硼酸酯化的（）-跳烯二烯酸酯的化学选择性硼基铜化反应受酯基控制，以得到3,3-二（频哪醇）-硼基链烯酸酯。用氢、氘、烷基、苄基或烯丙基卤化物以及异氰酸酯进行亲电捕获已被证明对α-官能化产物是有效的。含C-Br键的跳烯二烯酸酯的铜催化硼基铜化反应导致同时形成亚烷基-二硼基环丁烷骨架的闭环序列。我们进行了密度泛函理论计算以表征二硼基环丁烷形成的反应机理。该提议的关键步骤包括由烯烃取代基引导的选择性硼基铜化反应，随后是在钾阳离子辅助下朝向张力四元环的分子内C-C偶联反应。我们还分析了卤素离去基团的性质对选择性的影响。亚烷基环丁烷的多功能性已通过后官能化反应得到证明。
