Friedel−Crafts Acylation of Pyrroles and Indoles using 1,5-Diazabicyclo[4.3.0]non-5-ene (DBN) as a Nucleophilic Catalyst
作者:James E. Taylor、Matthew D. Jones、Jonathan M. J. Williams、Steven D. Bull
DOI:10.1021/ol1025348
日期:2010.12.17
1,5-Diazabicyclo[4.3.0]non-5-ene (DBN) has been shown to be an effective catalyst for the regioselective Friedel−Crafts C-acylation of pyrroles and indoles in high yields. A detailed mechanistic study implies that DBN is acting as a nucleophilic organocatalyst, with the X-ray crystal structure of a key N-acyl-amidine intermediate having been determined for the first time.
An Electrophilic Approach to the Palladium-Catalyzed Carbonylative C–H Functionalization of Heterocycles
作者:Jevgenijs Tjutrins、Bruce A. Arndtsen
DOI:10.1021/jacs.5b07098
日期:2015.9.23
highly electrophilic intermediates. Overall, this provides with an atom-economical and general synthetic route to generate aryl-(hetero)aryl ketones using stable reagents (aryl iodides and CO) and without the typical need to exploit pre-metalated heterocycles in carbonylativecoupling chemistry.
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。
Acylation of Pyrroles and their Free (N-H)-Derivatives<i>via</i>Palladium-Catalyzed Carbopalladation of Nitriles
AbstractAn efficient regioselective synthesis of 2‐acylpyrroles via palladium‐catalyzed addition of pyrroles with benzonitriles and subsequent hydrolysis is developed. The direct acylation reaction of protected as well as (NH)‐free pyrroles proceeded smoothly to afford 2‐acylpyrrole scaffolds of high biological interest.magnified image
Iodide as an Activating Agent for Acid Chlorides in Acylation Reactions
作者:Russell J. Wakeham、James E. Taylor、Steven D. Bull、James A. Morris、Jonathan M. J. Williams
DOI:10.1021/ol400035f
日期:2013.2.1
Acid chlorides can be activated using a simple iodide source to undergo nucleophilic attack from a variety of relatively weak nucleophiles. These include Friedel–Crafts acylation of N-methylpyrroles, N-acylation of sulfonamides, and acylation reactions of hindered phenol derivatives. The reaction is believed to proceed through a transient acidiodide intermediate.