Electrophilic Iron Catalyst Paired with a Lithium Cation Enables Selective Functionalization of Non‐Activated Aliphatic C−H Bonds via Metallocarbene Intermediates
Combining an electrophilic iron complex [Fe(F pda)(THF)]2 (3) [F pda=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
A Combined DFT and NMR Investigation of the Zinc Organometallic Intermediate Proposed in the<i>Syn</i>-Selective Tandem Chain Extension–Aldol Reaction of β-Keto Esters
作者:Karelle S. Aiken、Wilhelm A. Eger、Craig M. Williams、Carley M. Spencer、Charles K. Zercher
DOI:10.1021/jo3004925
日期:2012.7.20
esters provides an α-substituted γ-keto ester with an average syn:anti selectivity of 10:1. It is proposed that the reaction proceeds via a carbon–zinc bound organometallic intermediate potentially bearing mechanistic similarity to the Reformatsky reaction. Evidence, derived from control Reformatsky reactions and a study of the structure of the TCA intermediate utilizing DFT methods and NMR spectroscopy