A facile and efficient synthesis of aryl toluenesulfonhydrazides and aryl toluenesulfonates under solvent-free conditions

Chromatography-Free and Eco-Friendly Synthesis of Aryl Tosylates and Mesylates

“…With 10% K 2 CO 3 as base, their tosylation yielded the corresponding tosylates in excellent yields (entries 15-31), which demonstrates that our tosylation method is superior to others that gave somewhat lower yields of tosylates for phenols bearing electron-withdrawing groups. 3,5 The tosylation protocol with 15% NaOH as base worked efficiently for the synthesis of heteroaryl tosylates (entries 32-36) that have potential applications in the synthesis of biologically active molecules. With 15% NaOH as base, the tosylation of dihydric phenols and naphthalenols and bisphenols also gave good to excellent yields (entries 37-43).…”

“…Various methods have been reported to prepare aryl tosylates and mesylates. The methods for the synthesis of aryl tosylates include transition-metal-catalyzed sulfonylation, 3 solvent-free synthesis with 4 or without 5 microwave activation, heteropolyacid-catalyzed tosylation, 6 reaction of phenols with thiols using H 2 O 2 /POCl 3 system, 7 and tosyloxylation of anilides. 8 Aryl mesylates have been synthesized via one-pot demethylation-mesylation of aryl methyl ethers 9 and thermal decomposition of dry arenediazonium o-benzenedisulfonimides in methanesulfonic acid.…”

Facile synthesis of arylsulfonates from phenol derivatives and sulfonyl chlorides

“…Phenol derivatives with electron-withdrawing groups gave yields that could partially be rationalized using the electronic effect of the substituents. The electronic effect of substituents on the phenol derivatives in the reaction with tosyl chloride had previously been reported [5,18]. The presence of an electron-withdrawing group on the benzene ring makes the phenol derivative less nucleophilic.…”

“…Sulfonate esters can be formed through typical esterification of sulfonic acids, and through transesterifications involving an alcohol and sulfonate ester. Alternatively, sulfonate esters may be formed via the highly efficient nucleophilic acyl substitution reaction of alcohols and sulfonyl halides [2][3][4][5][6][7]. The efficiency of these reactions has led to the widespread use of sulfonate formation as a means to protect alcohols in the course of multistep syntheses [8].…”

Phenyl Benzenesulfonylhydrazides Exhibit Selective Indoleamine 2,3-Dioxygenase Inhibition with Potent in Vivo Pharmacodynamic Activity and Antitumor Efficacy

“…A precipitate was formed, collected by filtration, and washed with water and ether to give the desired product 47 as a white solid (0.250 g, 39%). 1 2-Amino-N′-(4-bromophenyl)-1H-benzimidazole-5-sulfonyl Hydrazide (48). To a solution of 2-amino-1H-benzimidazole-5-sulfonyl chloride (34) (0.410 g, 1.70 mmol) in 3 mL of dichloromethane and 1.5 mL of DMF was added 4-bromophenyl hydrazine (0.660 g, 3.50 mmol), and the reaction mixture was stirred at room temperature for 17 h. The resulting mixture was added to a saturated aqueous NaHCO 3 solution and stirred over 15 min.…”