ChemInform Abstract: Enantioselective Fluorination of 2‐Oxindoles by Structure‐Micro‐Tuned N‐Fluorobenzenesulfonamides.

Abstract

A series of N‐fluorobenzenesulfonamides such as (I) is synthesized and screened in the enantioselective fluorination of oxindole (IIa).

Monofluorination of Organic Compounds: 10 Years of Innovation

“…In 2014, Yang, Wu and co-workers described a similar system using a BINAP-derived palladium complex ( 47 ; see Scheme ). They performed the same reaction but observed higher enantioselectivities . They employed 4,4′-diF-NFSI as the fluorinating agent and obtained the asymmetric fluorinated oxindoles in excellent yields and high enantioselectivities.…”

“…Five new electrophilic fluorine sources have been developed since 2005. Stuart and co-workers have reported a fluoroiodane, a hypervalent iodine-based electrophilic reagent, while a sterically demanding version of NFSI has been described by Shibata, and a fluorinated analog was synthesized by Yang and co-workers . Gouverneur and co-workers reported chiral electrophilic fluorine sources based on the core of Selecfluor .…”

Modern Approaches for Asymmetric Construction of Carbon–Fluorine Quaternary Stereogenic Centers: Synthetic Challenges and Pharmaceutical Needs

“…Normally 2.5 mol % catalyst C49 or C50 was used for experiments, but in 2014, Yang and Wu published an interesting paper. 225 They prepared a series of substituted NFSI derivatives and examined the potency of these compounds as fluorinating reagents in this Pd-catalyzed fluorination of N-Boc-protected oxindole derivatives. They succeeded in reducing the amount of catalyst C50a to 0.5 mol % by using (4-F-C 6 H 4 SO 2 ) 2 NF in diethyl ether (Scheme 77c).…”

Atom Recombination of Difluorocarbene Enables 3-Fluorinated Oxindoles from 2-Aminoarylketones

“…On the other hand, in view of the potential therapeutic values, [40][41][42][43] the synthesis of 3-fluorooxindoles has attracted considerable attention, including fluorination of existing oxindoles, [44][45][46][47][48][49] fluoroarylation of diazoacetamides, 50 arylation of fluoracetamides [51][52] as well as the derivatization of 3-fluorooxindoles. [53][54] Based on the above conjecture, we envision 3-fluorinated oxindoles from 2-aminoarylketones which bear Page 2 of 20 CCS Chemistry both amino group as nucleophilic site and carbonyl group as electrophilic site could be accessible via an atom recombination of difluorocarbene as both C1 synthon and F1 reagent (Fig.…”