C-S coupling with nitro group as leaving group via simple inorganic salt catalysis

Synthesis and Biological Evaluation of Substituted 3‐Isoxazolethioethers as Antileishmanial and Antibacterial Agents

“…[15][16][17] The nitroarenes are widely cited to undergo direct nucleophilic reaction with thiols under different conditions such as in the presence of Cs 2 CO 3 in DMSO or Magnesium methoxide or CuI and K 2 CO 3 or K 3 PO 4 and crown ether (Figure 2). [18][19][20][21] During our studies, Averina et al citing our previous findings, disclosed the results of their work on the S N Ar reactions with different nucleophiles including phenols and thiophenols on 5-nitroisoxazoles and 3-nitroisoxazoles in the presence of DIPEA. [22] Independent of their report, to meet our objective of developing broader SAR, we have earlier initiated investigations by performing the reactions of 3-nitroisoxazoles with thiols in inorganic bases followed by organic bases and discovered that in the presence of 0.5 equiv.…”

“…The nitroarenes are widely cited to undergo direct nucleophilic reaction with thiols under different conditions such as in the presence of Cs 2 CO 3 in DMSO or Magnesium methoxide or CuI and K 2 CO 3 or K 3 PO 4 and crown ether (Figure 2). [18–21] During our studies, Averina et al. citing our previous findings, disclosed the results of their work on the S N Ar reactions with different nucleophiles including phenols and thiophenols on 5‐nitroisoxazoles and 3‐nitroisoxazoles in the presence of DIPEA [22] .…”

“…Initially, in a pilot reaction methyl 5-(4-chlorophenyl)-3-nitroisoxazole-4-carboxylate (1 ac) was treated with 4-chlorothiophenol (2 c) in the presence of the inorganic base K 3 PO 4 (10 mol %) and crown ether (20 mol %) as reported in the literature. [21] The reaction was completed in 24 h to offer the required 3-isoxazole derivative 3 acc in 63 % yield (Table 1). Titrating the amount of the base revealed that with 3.0 equiv.…”

Dithiol‐Activated Bioorthogonal Chemistry for Endoplasmic Reticulum‐Targeted Synergistic Chemophototherapy

“…However, the case of dithiols is different. The intramolecular hydrogen bonding [45] between the nitro group and the remaining terminal À SH favors the second step S N Ar, which involves intramolecular cyclization and formation of intermediate Meisenheimer complex [16,46] that is stabilized by the electron deficient nature of BTD heterocycle and leads to the departure of nitro group.…”

Fe-Catalyzed Synthesis of Sulfide-Based Aromatic Primary Amines in Water Promoted by Sodium-Ascorbate

“…(4-nitrophenyl)(ptolyl)sulfane (4aa) and deuterated 4-methylbenzenethiol (2a-d1) were synthesized according to the reported literature. [20,25] Solvents and chemicals were bought from commercial sources and used directly unless otherwise stated. 4.2 General procedure for the synthesis of sulfidebased aromatic primary amine A solution of nitroaryl fluorides (0.4 mmol), thiols (0.6 mmol), Fe(acac) 3 (10 mol%), 2,2'-bipyridine (10 mol%), K 2 CO 3 (0.6 mmol), Na-ascorbate (1.2 mmol) and TBAB (0.4 mmol) in deionized H 2 O (2 mL) was stirred in a 10 mL well-sealed thick-walled glass tube at 110 ℃ under N 2 for 16 h. The reaction mixture was cooled down and extracted with dichloromethane (10 mL) for three times.…”