Reaction of [As(NMe2)(3)] with CyNH2 (1:1 equivalents), followed by the add
ition of [CyNHLi] (1 equivalent) gives the heterobimetallic cage complex [{
As-2(NCy)(4)}(2)Li-4] the first example of a complex containing an imido As
(III) anion; the missing link in a series of Group 15 anions of the type [{
E-2(NCy)(4)}](2-) (E = Bi, Sb and P).