Electrophilic Iron Catalyst Paired with a Lithium Cation Enables Selective Functionalization of Non‐Activated Aliphatic C−H Bonds via Metallocarbene Intermediates |
| |
Authors: | Alberto Hernn‐Gmez Mnica Rodríguez Teodor Parella Miquel Costas |
| |
Institution: | Alberto Hernán‐Gómez,Mònica Rodríguez,Teodor Parella,Miquel Costas |
| |
Abstract: | Combining an electrophilic iron complex Fe(Fpda)(THF)]2 ( 3 ) Fpda=N,N′‐bis(pentafluorophenyl)‐o‐phenylenediamide] with the pre‐activation of α‐alkyl‐substituted α‐diazoesters reagents by LiAl(ORF)4 ORF=(OC(CF3)3] provides unprecedented access to selective iron‐catalyzed intramolecular functionalization of strong alkyl C(sp3)?H bonds. Reactions occur at 25 °C via α‐alkyl‐metallocarbene intermediates, and with activity/selectivity levels similar to those of rhodium carboxylate catalysts. Mechanistic investigations reveal a crucial role of the lithium cation in the rate‐determining formation of the electrophilic iron‐carbene intermediate, which then proceeds by concerted insertion into the C?H bond. |
| |
Keywords: | C-H-Aktivierung Carbene Eisen Lithium Reaktionsmechanismen |
|