Radical‐Nucleophilic Aromatic Substitution

Rossi, Roberto A.; Guastavino, Javier Fernando; Budén, María Eugenia

doi:10.1002/9781118754887.ch10

Cited by 13 publications

(5 citation statements)

References 129 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Radical nucleophilic substitution involving electron-transfer (ET) steps (S RN 1) is a cyclic process with radicals and radical anions as intermediates. In the S RN 1 reactions, carbanions and anions derived from heteroatoms can be used as nucleophiles to form new C–C or C–heteroatom bonds.…”

Section: Introductionmentioning

confidence: 99%

Synthesis of Dibenzosultams by “Transition-Metal-Free” Photoinduced Intramolecular Arylation of N-Aryl-2-halobenzenesulfonamides

et al. 2016

Self Cite

View full text Add to dashboard Cite

A new and general synthetic route to prepare dibenzosultams is here reported. This approach involves the synthesis of N-aryl-2-halobenzenesulfonamides (3), followed by intramolecular C-C photoinduced arylation under soft conditions without the use of "Transition Metal". The photostimulated reactions exhibit very good tolerance to different substituent groups with good to excellent isolated yields (42-98%) of products. Moreover, it is shown that LED (λ = 395 nm) is an efficient light energy source to initiate efficiently the reactions. Theoretical inspection of the mechanism was made to probe the involvement of the radical-anion SRN1 process.

show abstract

Section: Introductionmentioning

confidence: 99%

Synthesis of Dibenzosultams by “Transition-Metal-Free” Photoinduced Intramolecular Arylation of N-Aryl-2-halobenzenesulfonamides

et al. 2016

Self Cite

View full text Add to dashboard Cite

show abstract

“…In nucleophilic aromatic substitution (S N Ar) reactions, 2 where an sp 2 hybridized aromatic carbon with leaving group (X) is substituted by a nucleophile (Nu), several mechanistic scenarios can be conceived: two-step pathways through a Meisenheimer complex (Scheme 1A) or a benzyne (Scheme 1B) as the reaction intermediate are commonly accepted reaction mechanisms, whereas a concerted process (cS N Ar) has been considered as a rare case (Scheme 1C). [3][4][5][6] Recently, Jacobsen and co-workers revealed through experimental and computational studies that the ability of the leaving group greatly affects the reaction course of nucleophilic aromatic substitution reactions, implying that there might be more cases of cS N Ar than expected. 7,8 Our group has also recently developed the intra-and intermolecular nucleophilic amination of methoxy(hetero)arenes by NaH in the presence of LiI in THF (Scheme 2), where a methoxy group, which is generally considered as a poor leaving group, is substituted with sodium (lithium) amide nucleophile presumably under the cS N Ar mechanism.…”

mentioning

confidence: 99%

Leaving Group Ability in Nucleophilic Aromatic Amination by Sodium Hydride–Lithium Iodide Composite

et al. 2019

View full text Add to dashboard Cite

show abstract

“…[7,8] Such a process provides thus an opportunity to investigate both the formation and the dissociation of radical anion intermediates and the factors controlling them. Radical anions are indeed fundamental intermediates in many relevant chemical and biochemical processes including, among others, the formation of Grignard reagents, [9] S RN 1 reactions, [10] DNA damage, [11] and enzymatic reactions. [12] Radical anions are also used for the synthesis of relevant materials for many applications.…”

Section: Introductionmentioning

confidence: 99%

Dissociative Electron Transfer to N‐(Arylthio)phthalimides: Factors Affecting the Formation and Dissociation of Radical Anions

Saley,

Hamed,

Houmam

2024

ChemElectroChem

View full text Add to dashboard Cite

A series of chemically and biologically relevant N‐(arylthio)phthalimides is synthesized and its electrochemical reduction investigated. The results of the electrochemical study are analysed through application of Savéant's dissociative electron transfer theory and with the assistance of theoretical calculations. Reduction of all investigated N‐(arylthio)phthalimides leads to the corresponding radical anions, followed by the ejection of the phthalimide anion resulting from the dissociation of the N−S chemical bond. This stepwise electron transfer mechanism is evidenced by the electrochemical data which allow determination of the standard reduction potentials of all compounds. In the formation of the N‐(arylthio)phthalimide radical anions, the theoretical calculations show that the incoming electron, is hosted by the phthalimidyl group indicating a homolytic dissociation mechanism. The dissociation rate constants of the radical anions are deduced and show that upon changing the substituent from the MeO, to Me, H, F, Cl and Br the dissociation becomes faster. A good correlation with the Hammett substituent constants is also obtained. Application of Savéant's theory through determination of the associated driving force and the intrinsic barrier energies help rationalize the observed results and show that the change in the dissociation rate constant depends mainly on the standard reduction potential of the parent compounds.

show abstract

Radical‐Nucleophilic Aromatic Substitution

Cited by 13 publications

References 129 publications

Synthesis of Dibenzosultams by “Transition-Metal-Free” Photoinduced Intramolecular Arylation of N-Aryl-2-halobenzenesulfonamides

Synthesis of Dibenzosultams by “Transition-Metal-Free” Photoinduced Intramolecular Arylation of N-Aryl-2-halobenzenesulfonamides

Leaving Group Ability in Nucleophilic Aromatic Amination by Sodium Hydride–Lithium Iodide Composite

Dissociative Electron Transfer to N‐(Arylthio)phthalimides: Factors Affecting the Formation and Dissociation of Radical Anions

Contact Info

Product

Resources

About