Some transition-metal complexes of 1,3,2-dithiarsolane

Abstract

Reaction of a range of transition-metal carbonyl anions [M]^– with 2-chloro-1,3,2-dithiarsolane results in the formation of the metalloarsines [M–A[graphic omitted]]{M^–=[Mo(CO)₃(η-C₅H₅)]^–, [W(CO)₃(η-C₅H₅)]^–, [Fe(CO)₂(η-C₅H₅)]^–, [Mn(CO)₅]^–, or [Re(CO)₅]^–}. There is no indication on an n.m.r. time-scale of pyramidal inversion about the arsenic atom in these complexes. Photolysis of [Mo(σ-A[graphic omitted])(CO)₃(η-C₅H₅)] causes elimination of carbon monoxide and formation of [Mo(η²-A[graphic omitted])(CO)₂(η-C₅H₅)] in which the dithiarsolane ring behaves as a dihapto, formally, three-electron donor. The reaction of 2-chloro-1,3,2-dithiarsolane with [Co(CO)₄]^– produces the dihapto product [Co(η²-[graphic omitted])(CO)₃] directly.