NiFe2O4 as a magnetically recoverable nanocatalyst for odourless C–S bond formation via the cleavage of C–O bond in the presence of S8 under mild and green conditions

Abstract

We present green methodologies for one‐pot and odourless syntheses of unsymmetric and symmetric diaryl sulfides via C─O bond activation using NiFe2O4 magnetic nanoparticles as a reusable heterogeneous nanocatalyst. The synthesis of unsymmetric sulfides is performed using the cross‐coupling reaction of phenolic esters such as acetates, triflates and tosylates with arylboronic acid/S8 or triphenyltin chloride/S8 as thiolating agents in the presence of base and NiFe2O4 magnetic nanoparticles as a catalyst in poly(ethylene glycol) as solvent at 60–85°C. Also, the synthesis of symmetric diaryl sulfides from phenolic compounds using S8 as the sulfur source and NiFe2O4 as catalyst in dimethylformamide at 120°C is described. Using these protocols, the syntheses of various unsymmetric and symmetric sulfides become easier than using the available protocols due to the use of a magnetically reusable bimetallic nanocatalyst and avoiding the use of thiols and aryl halides.