N→As intramolecularly coordinated organoarsenic(III) chalcogenides: Isolation of terminal As–S and As–Se bonds

Unprecedented NCN – intramolecularly chelated organoarsenic(III) sulfide and selenide LAsE (where L = [2,6-(Me2NCH2)2C6H3]− and E = S (2) or Se (3)) were prepared by the reaction of the parent chloride LAsCl2 (1) with Li2E. Analogously, the reaction of NC chelated compound L′AsCl2 (4) (where L′ = [2-(2′,6′-i-Pr2C6H3)Ndouble bond; length as m-dashCH)C6H4]−) with Li2S gave the corresponding sulfide L′AsS (5). The molecular structures of 3 and 4 were established in the solid state using X-ray diffraction technique.