Prototypical Phosphine Complexes of Antimony(III)

Complexes of the generic formula [Cln(PR3)mSb](3–n)+ (n = 1, 2, 3, or 4 and m = 1 or 2) have been prepared featuring [ClSb]2+, [Cl2Sb]1+, Cl3Sb, or [Cl4Sb]1− as acceptors with one or two phosphine ligands {PMe3, PPh3, PCy3 (Cy = C6H11)}. The solid-state structures of the complexes reveal foundational features that define the coordination chemistry of a lone pair bearing stibine acceptor site. The experimental observations are interpreted with dispersion-corrected density functional theory calculations to develop an understanding of the bonding and structural diversity.