Iuliano Veronica, Talotta Carmen, De Rosa Margherita, Soriente Annunziata, Neri Placido, Rescifina Antonio, Floresta Giuseppe, Gaeta Carmine
Laboratory of Supramolecular Chemistry, Dipartimento di Chimica e Biologia "A. Zambelli", Università di Salerno, Via Giovanni Paolo II 132, I-84084 Fisciano, Salerno, Italy.
Dipartimento di Scienze del Farmaco, Università di Catania, Viale Andrea Doria 6, 95125 Catania, Italy.
Org Lett. 2023 Sep 8;25(35):6464-6468. doi: 10.1021/acs.orglett.3c01935. Epub 2023 Aug 29.
Friedel-Crafts benzoylation of -methylpyrrole can run inside the confined space of the hexameric resorcinarene capsule . The bridged water molecules at the corner of act as H-bonding donor groups to polarize the C-Cl bond of benzoyl chlorides -. Confinement effects on the regiochemistry of the FC benzoylation of -methylpyrrole are observed. The nature of the -substituents of - and their ability to establish H-bonds with the water molecules of work synergistically with the steric constrictions imposed by the capsule to drive the regiochemistry of products -. QM investigations indicate that inside the cavity of , the FC benzoylation of has a bimolecular concerted S2 mechanism, appropriately, above-plane nucleophilic vinylic substitution (SVπ)─supported by H-bonding interactions between water molecules and both the leaving Cl atom and the carbonyl group.
α-甲基吡咯的傅克苯甲酰化反应可以在六聚间苯二酚杯芳烃胶囊的受限空间内进行。胶囊角落处的桥连水分子作为氢键供体基团，使苯甲酰氯的C-Cl键极化。观察到了受限效应对α-甲基吡咯傅克苯甲酰化区域化学的影响。α-取代基的性质及其与胶囊水分子形成氢键的能力，与胶囊施加的空间限制协同作用，驱动产物的区域化学。量子力学研究表明，在胶囊腔内，α-甲基吡咯的傅克苯甲酰化反应具有双分子协同S2机制，确切地说是平面上亲核乙烯基取代（SVπ），这得到了水分子与离去的Cl原子和羰基之间氢键相互作用的支持。
