A synthesis of sulfoxides and disulfides under classical and ultrasonic conditions in presence of recoverable inorganic-organic hybrid magnetism nanocatalysts Fe3O4@Tryptophan-M (M: Cu, Co and Fe)

Three inorganic-organic hybrid magnetic nanocatalysts have been reported as new catalysts for the synthesis of sulfoxides and disulfides. Also, the effect of ultrasound irradiation on the synthesis of sulfoxides and disulfides was checked. The time of reaction was reduced and the yield was improved in the ultrasonic method compared with the conventional method. Magnetic nanoparticles were used for several times without any significant change in activity. Easy synthesis, high catalytic activity, mild reaction conditions, eco-friendliness, ease of separation of the catalysts and good reusability are their advantages. (C) 2019 Elsevier Ltd. All rights reserved.