Synthesis and fungicidal activity of some alkyl – 2,4 – dinitrobenzenesulfenate esters

Abstract

2,4-dinitrobenzenesulfenyl chloride was prepared by reacting 2,4-dinitrochlorobenzene with benzyl mercaptan and subsequently cracking the formed 2,4-dinitrophenyl benzyl sulphide with sulfuryl chloride. The prepared 2,4-dinitrobenzenesulfenyl chloride reacted with series of primary alcohols in the presence of pyridine to give alkyl-2,4-dinitrobenzenesulfenate esters. The synthesized compounds were characterized by elemental analysis, thin layer chromatography (TLC), fourier-transform infrared, 1H and 13C nuclear magnetic resonance
spectroscopic techniques. In vitro fungicidal assay of these alkyl sulfenate esters against Aspergillus flavus, Rhizopus stolonifer and Fusarium oxysporum showed that all the synthesized sulfenate esters were fungicidal. Increase in chain length of the alkyl substituents was found to reduce the fungicidal activity of the alkyl sulfenate esters. Presence of an hydroxyl group increased the fungicidal activity of ethyl-2,4-dinitrobenzenesulfenate by 5-to 10-fold.