Iron tris(dimethyldithiocarbamate)

Iron tris(dimethyldithiocarbamate) is the coordination complex of iron with dimethyldithiocarbamate with the formula Fe(S₂CNMe₂)₃ (Me = methyl). It is marketed as a fungicide.^[3]

Iron tris(dimethyldithiocarbamate)

Names
IUPAC name Tris(dimethyldithiocarbamato)iron
Other names Ferric dimethyl dithiocarbamate, Ferbam
Identifiers
CAS Number	14484-64-1
3D model (JSmol)	coordination form: Interactive image ionic form: Interactive image
ChEBI	CHEBI:5015
ChemSpider	24884
ECHA InfoCard	100.034.970
EC Number	238-484-2
KEGG	C11223
PubChem CID	26710
RTECS number	NO8750000
UNII	SKM8W5154H
UN number	3077, 2771
CompTox Dashboard (EPA)	DTXSID8020624
InChI InChI=1S/3C3H7NS2.Fe/c3*1-4(2)3(5)6;/h3*1-2H3,(H,5,6);/q;;;+3/p-3 Key: WHDGWKAJBYRJJL-UHFFFAOYSA-K
SMILES coordination form: CN(C)C(S1)S[Fe]123(SC(S2)N(C)C)SC(S3)N(C)C ionic form: CN(C)C(=S)[S-].[Fe+3].CN(C)C(=S)[S-].CN(C)C(=S)[S-]
Properties
Chemical formula	[(CH3)2NCS2]3Fe
Molar mass	416.5 g/mol
Appearance	Dark brown to black, odorless solid[1]
Density	1.52 g/cm3
Melting point	Decomposes above 180 °C (356 °F)[1]
Boiling point	Decomposes[1]
Solubility in water	0.01% (20 °C)[1]
Hazards
Occupational safety and health (OHS/OSH):
Main hazards	Reacts with strong oxidizers, moisture[1]
Lethal dose or concentration (LD, LC):
LD50 (median dose)	3000 mg/kg (rabbit, oral) 2000 mg/kg (guinea pig, oral) 1130 mg/kg (rat, oral) 3400 mg/kg (mouse, oral)[2]
NIOSH (US health exposure limits):
PEL (Permissible)	TWA 15 mg/m3[1]
REL (Recommended)	TWA 10 mg/m3[1]
IDLH (Immediate danger)	800 mg/m3[1]
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Synthesis, structure, bonding

Iron tris(dithiocarbamate)s are typically are prepared by salt metathesis reactions.^[3]

Iron tris(dimethyldithiocarbamate) is an octahedral coordination complex of iron(III) with D₃ symmetry.^[4]

Spin crossover (SCO) was first observed in 1931 by Cambi et al. who discovered anomalous magnetic behavior for the tris(N,N-dialkyldithiocarbamatoiron(III) complexes.^[5] The spin states of these complexes are sensitive to the nature of the amine substituents.^[6]

Reactions

Iron tris(dithiocarbamate)s react with nitric oxide to give a nitrosyl complex:

Fe(dtc)₃ + NO → Fe(dtc)₂NO + 0.5 (dtc)₂

This efficient chemical trapping reaction provides a means to detect NO.^[7]

Reflecting the strongly donating properties of dithiocarbamate ligands, iron tris(dithiocarbamate)s oxidize at relatively mild potentials to give isolable iron(IV) derivatives [Fe(S₂CNR₂)₃]⁺.^[8]

Iron tris(dithiocarbamate)s react with hydrochloric acid to give the pentacoordinate chloride:^[9]

Fe(dtc)₃ + HCl → Fe(dtc)₂Cl + Hdtc

Safety

The U.S. Occupational Safety and Health Administration (OSHA) has set the legal (permissible exposure limit) for ferbam exposure in the workplace as 15 mg/m³ over an 8-hour workday. The U.S. National Institute for Occupational Safety and Health (NIOSH) has set a recommended exposure limit (REL) of 1 mg/m³ over an 8-hour workday. At levels of 800 mg/m³, ferbam is immediately dangerous to life and health.^[1]

See also

• Zinc dimethyldithiocarbamate - a related dimethyldithiocarbamate complex of zinc
• Nickel bis(dimethyldithiocarbamate) - a related dimethyldithiocarbamate complex of nickel
• Iron tris(diethyldithiocarbamate) - a related dimethyldithiocarbamate complex of iron

References

1. NIOSH Pocket Guide to Chemical Hazards. "#0286". National Institute for Occupational Safety and Health (NIOSH).
2. "Ferbam". Immediately Dangerous to Life or Health Concentrations (IDLH). National Institute for Occupational Safety and Health (NIOSH).
3. D. Coucouvanis (2007). "The Chemistry of the Dithioacid and 1,1-Dithiolate Complexes". Progress in Inorganic Chemistry. Vol. 11. pp. 233–371. doi:10.1002/9780470166123.ch4. ISBN 978-0-470-16612-3.
4. J. Albertsson; Å. Oskarsson (1977). "Compounds with intermediate spin. I. The crystal structure of tris(N,N-dimethyldithiocarbamato)iron(III) at 150 and 295 K". Acta Crystallographica Section B. 33 (6): 1871–1877. Bibcode:1977AcCrB..33.1871A. doi:10.1107/s0567740877007237.
5. L. Cambi; L and L. Szego (1931). "Über die magnetische Susceptibilität der komplexen Verbindungen". Chem. Ber. Dtsch. Ges. 64 (10): 2591. doi:10.1002/cber.19310641002.
6. P. Gütlich; H.A. Goodwin (2004). Spin Crossover in Transition Metal Compounds I. Springer Berlin. ISBN 978-3-540-40396-8.
7. Fujii, S.; Yoshimura, T. (2000). "A New Trend in Iron–Dithiocarbamate Complexes: as an Endogenous NO Trapping Agent". Coordination Chemistry Reviews. 198: 89–99. doi:10.1016/S0010-8545(99)00196-4.
8. Pasek, E. A.; Straub, D. K. (1972). "Tris(N,N-Disubstituted Dithiocarbamato)iron(IV) Tetrafluoroborates". Inorganic Chemistry. 11 (2): 259–263. doi:10.1021/ic50108a012.
9. Martin, R. L.; White, A. H. (1967). "A Novel Series of fFive-Coordinated Iron(III) Complexes with the Square-Pyramidal Configuration and Spin, S = 3/2". Inorganic Chemistry. 6 (4): 712–717. doi:10.1021/ic50050a016.