One bromination protocol employs a 0.2 equivalent Cu ( I ) / Cu ( II ) mixture with additional amounts of the bidentate ligand phenanthroline and phase-transfer catalyst dibenzo-18-crown-6:
22.
The complex Mo ( S " CH = CH " S ) 3 is also trigonal prismatic, with each S " CH = CH " S group acting as a bidentate ligand with two sulfur atoms binding the metal atom.
23.
The nitrogen atoms on its pyridine rings, like those of its isomer 4-pyridylnicotinamide, can donate their electron lone pairs to metal cations, allowing it to bridge metal centers and act as a bidentate ligand in coordination polymers.
24.
An example of chelating nitrite ( 3 ) was found in [ Cu ( bipy ) 2 ( O 2 N ) ] NO 3 " bipy " is the bidentate ligand 2, 22-bypyridyl, with the two bipy ligands occupying four coordination sites on the copper ion, so that the nitrite is forced to occupy two sites in order to achieve an octahedral environment around the copper ion.
