4-(Methylthio)benzaldehyde is a building block for the synthesis of various pharmaceutical and biologically active compounds. It can be used for the synthesis of sulfur-containing terpyridine ligands. It is the intermediate for the synthesis of a class of pyrrole derivatives showing analgesic/anti-inflammatory activity.
In the standard synthetic method, diphenyl sulfoxide (2.2 g, 0.01 mol) is mixed with brominated silica (18.18 g, 40 mmol Br/g silica) in a nonprotonic solvent such as dichloromethane (2 mL) or carbon tetrachloride. The reaction was carried out at room temperature while atmospheric water needed to be removed for 5 min. Upon completion of the reaction, the product was separated by simple filtration, followed by evaporation of the solvent to give diphenyl sulfide in its pure state (yield 1.84 g, 99%).
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