Pentaatomic heteroaromatic cations. 18. Acylation of pyrrole and N-methylpyrrole with 1,3-benzoxathiolium tetrafluoroborates. A high-yield method for the synthesis of diacylpyrroles
Palladium catalyzed carbonylative generation of potent, pyridine-based acylating electrophiles for the functionalization of arenes to ketones
作者:Yi Liu、Angela M. Kaiser、Bruce A. Arndtsen
DOI:10.1039/d0sc03129a
日期:——
ultimate elimination of a new class of potent Friedel–Crafts acylating agent: N-acyl pyridinium salts. The latter can be exploited to modulate reactivity and selectivity in carbonylative arene functionalization chemistry, and allow the efficient synthesis of ketones with a diverse array of (hetero)arenes.
Insights into the Friedel–Crafts Benzoylation of <i>N</i>-Methylpyrrole inside the Confined Space of the Self-Assembled Resorcinarene Capsule
作者:Veronica Iuliano、Carmen Talotta、Margherita De Rosa、Annunziata Soriente、Placido Neri、Antonio Rescifina、Giuseppe Floresta、Carmine Gaeta
DOI:10.1021/acs.orglett.3c01935
日期:2023.9.8
Friedel–Crafts benzoylation of N-methylpyrrole 2 can run inside the confined space of the hexameric resorcinarene capsule C. The bridged water molecules at the corner of C act as H-bonding donor groups to polarize the C–Cl bond of benzoyl chlorides 3a–f. Confinement effects on the regiochemistry of the FC benzoylation of N-methylpyrrole are observed. The nature of the para-substituents of 3a–f and
N-甲基吡咯2的弗里德尔-克来福特苯甲酰化可以在六聚间苯二酚胶囊C的有限空间内进行。C角处的桥联水分子充当氢键供体基团,使苯甲酰氯3a – f的 C-Cl 键极化。观察到N-甲基吡咯 FC 苯甲酰化区域化学的限制效应。3a – f的对位取代基的性质及其与C的水分子建立氢键的能力与胶囊施加的空间收缩协同作用,驱动产物4a – f的区域化学。量子力学研究表明,在C的空腔内, 2的 FC 苯甲酰化具有双分子协同 S N 2 机制,相应地,平面上亲核乙烯基取代 (S N Vπ) — 由水分子和水分子之间的氢键相互作用支持。留下Cl原子和羰基。
BARBERO, MARGHERITA;CADAMURO, SILVANO;DEGANI, IACOPO;FOCHI, RITA;GATTI, A+, J. ORG. CHEM., 53,(1988) N 10, 2245-2250
Pentaatomic heteroaromatic cations. 18. Acylation of pyrrole and N-methylpyrrole with 1,3-benzoxathiolium tetrafluoroborates. A high-yield method for the synthesis of diacylpyrroles