Tripodal ligand

They are popular in research in the areas of coordination chemistry and homogeneous catalysis.

In their coordination complexes with an octahedral molecular geometry the tridentate tripod ligands occupy one face, leading to a fixed facial (or fac) geometry.

The tetradentate tripodal ligands occupy four contiguous sites, leaving two cis positions available on the octahedral metal center.

One tripodal ligand of commercial significance is nitrilotriacetate, N(CH2CO2−)3 because it is cheaply produced and has a high affinity for divalent metal ions.

Many kinds of donor groups have been incorporated into the arms of tripodal ligands, including amido (R2N−),[2] and N-heterocyclic carbenes.

Motifs for complexation of tri- and tetradentate tripodal ligands
Structure of [Ni( TACH )(H 2 O) 3 ] 2+ (color code: blue = nitrogen, red = oxygen, dark blue = nickel). [ 3 ]