Tris(dimethyldithioarsinato) complexes of Group 13 metals,M(S 2 AsMe 2 ) 3 (M = Al,Ga,In,Tl)

The tris(dimethyldithioarsinato) complexes M(S₂AsMe₂)₃ (M = Al, Ga, In and Tl) have been prepared from NaS₂AsMe₂·2H₂O as anhydrous powders. The Al and Ga, but not the In and Tl, complexes add water molecules seen in the IR(KBr) spectra. The Al and Ga coordinate, while the In and Tl complexes attract and polarize water in CDCl₃ resulting in more than one signal for H₂O in the ¹H NMR spectra. All four complexes are desulfurized by Ph₃P but the expected M(SAsMe₂)₃ are unstable and decompose to Me₂As-S-AsMe₂ and other products.