CHM 401

 

Nomenclature of transition metal complexes

Cationic and Neutral complexes:

1) ligands are listed in alphabetical order using systematic name except:

a) if the ligand name ends in -ide, -ate, or ite, drop the final e and and add an o

b) others : O2– oxo; OH hydroxo; CN cyano; O22– peroxo; NH3 ammine; H2O aqua; NO nitrosyl; CO carbonyl

2) the number of times a ligand appears is prefixed to the ligand using

Stoichiometry

Prefix

Alternate Prefix

use the second alternative if the preferred prefix gives an ambiguity

2

bi (preferred) or di

bis

 

3

tri

tris

 

4

tetra

tetrakis

 

5

penta

pentakis

 

6

hexa

hexakis

 

3) structural information prefixes ligands, and can be for each ligand if necessary

cis-; trans-; fac-; mer-; μ- (ligand bridges two metals);

ηx– (x = number of C bonded to metal in an organic ligand)

4) metal is last followed by parentheses with the formal oxidation state in roman numerals

5) if cationic, counterion is the second word

Examples

Co(NH3)6Cl3

hexaamminecobalt(III) chloride

[Co(NH3)5Cl]Cl2

pentaamminechlorocobalt(III) chloride

[Co(NH3)4Cl2]Cl

cis-tetraamminedichlorocobalt(III) chloride

trans-tetraamminedichlorocobalt(III) chloride

[Co(NH3)3Cl3]

fac-triamminetrichlorocobalt(III)

mer-triamminetrichlorocobalt(III)

CuCl2(CH3NH2)2

cis-dichlorobis(methylamine)copper(II)

Ni(CO)4

tetracarbonylnickel(0)

PtCl2(CH2=CH2)

dichloro-η2-etheneplatinum(II)

(C5H5)2Fe

bis(η5-cyclopentadienyl)iron(II) [more commonly known as ferrocene]

Br2Pt-(S(CH3)2)2-PtBr2

bis(μ-dimethylsulfido)bis(dibromoplatinum(II))


Anions:

1) counterion is first word

2) use cationic rules except add -ate to the end of the metal before the oxidation state info sometimes can use the Latin root

Examples

K2[OsCl5N]

potassium pentachloronitridoosmate(VI)

Na3[Ag(S2O3)2]

sodium bis(thiosulfato)argentate(I)

Na2[Fe(CN)5NO]

sodium pentacyanonitrosylferrate(III)