Diphenyl thiophenyl arsine

The invention comprises compounds of formula where R1 is a benzyl radical or a substituted or unsubstituted alkyl or aryl radical and R2 is a substituted or unsubstituted aryl radical, a benzyl radical, a saturated hydrocarbon radical or a halogen. Specified compounds include diphenyl thiophenyl arsine, and diphenyl(1 - thio - 2 - carbomethoxyphenyl) arsine. They may be prepared by reacting a phenylhalo-arsine of formula C6H5Hs(R2)X with an alkyl metal mercaptide of formula R1SM where R1 and R1 are as above defined, X is halogen and M is an alkali metal. The reaction is carried out in a solvent in which the reactants are soluble, e.g. ethanol. They may be used in pesticidal and fungicidal compositions (see Division A5).ALSO:Pesticidal compositions comprise a compound of formula p where R1 is a benzyl radical or a substituted or unsubstituted alkyl or aryl radical and R2 is a substituted or unsubstituted aryl radical, a benzyl radical, a saturated hydrocarbon radical or a halogen associated with a solvent, emulsifier, wetting agent dispersant, inert powder and/or an anti-foaming agent. Specified are (a) a wettable powder comprising diphenyl thiobenzyl arsine, kieselguhr and an alkyl aryl sulphonate, and (b) a dusting powder comprising diphenyl thiophenyl arsine and talc.