We report the synthesis and structure of arsenic (III) and tin(IV) adducts of the hydrotris(methimazolyl)borate anion (Tm-Me). Both species are found to be [E(kappa(3)Tm(Me))(2)](n+) anions (E = As, n = 1; E = Sn, n = 2). Comparisons are made between each of these species and the compounds formed with their heavier and larger group partners bismuth and lead. Due to the remarkable flexibility in the soft scorpionate ligand we were unable to form a charge-separated species analogous to that reported by Parkin for the phenyl analogue (Tm-Ph). Attempts to prepare the tin(II) adduct curiously produced the tin(IV) product [Sn(kappa(3)Tm(Me))(2)][Tm-Me](2) even when the reaction was carried out under inert atmospheres.
- TRIPODAL LIGANDS