Mixed Donor LigandsBased in part on the article Mixed Donor Ligands by Nikolay N. Gerasimchuk & Kristin Bowman‐James which appeared in theEncyclopedia of Inorganic Chemistry, First Edition.

Abstract

Mixed donor ligands are extremely common and are linear, branched, or cyclic molecules that contain at least two different donor groups capable of chelation to metal ions by those groups as polydentate ligands. The most common donor atoms met are N, O, S, and P, although other donors such as group 14 elements (including C) are known. Whereas mixed donor ligands are considered classically to involve groups with different donor atoms (such as N from an amine and O from a carboxylate), different classes of donor groups of one type of donor atom (such as pyridine and amine groups) also effectively produce mixed donor ligands. The coordination chemistry of mixed donor ligands is very extensive; all metal ions form mixed donor complexes, and the number of isomers possible for complexes with mixed donors is usually greater than with symmetrical ligands of comparable denticity.

Hydrogen and Halogen Bond Mediated Coordination Polymers of Chloro-Substituted Pyrazin-2-Amine Copper(I) Bromide Complexes

“…This fact is due to reproducible outcomes, that reflect the strong metal-ligand coordination bonds, and can be achieved with the judicious choice of organic ligands and metal-ions [14][15][16][17][18][19][20][21]. In this context, for example, O-and N-atoms are typical donors for the coordination bond formation; the former are derived from functional groups such as -COOH, -SO 3 H and phosphonates [22][23][24], and the latter primarily from N-heterocycles [25]. The combined use of these two groups render ligands a strong coordinating ability, and are well-known for the preparation of homometallic and heterometallic coordination compounds [25].…”

“…In this context, for example, O-and N-atoms are typical donors for the coordination bond formation; the former are derived from functional groups such as -COOH, -SO 3 H and phosphonates [22][23][24], and the latter primarily from N-heterocycles [25]. The combined use of these two groups render ligands a strong coordinating ability, and are well-known for the preparation of homometallic and heterometallic coordination compounds [25].…”