Nickel bis(dimethylglyoximate)

Nickel bis(dimethylglyoximate)
Names
	IUPAC name nickel;N-[(Z)-3-nitrosobut-2-en-2-yl]hydroxylamine
	Other names Bis(butanedione dioximato)nickel
Identifiers
CAS Number	13478-93-8 ;
3D model (JSmol)	Interactive image;
ChemSpider	4584372;
EC Number	236-782-7;
PubChem CID	5475696;
UNII	7CZ5340YUM ;
	InChI InChI=1S/2C4H8N2O2.Ni/c21-3(5-7)4(2)6-8;/h25,7H,1-2H3;/b2*4-3-; Key: CNOULSXJEKYGTK-FDGPNNRMSA-N;
	SMILES CC(=C(C)N=O)NO.CC(=C(C)N=O)NO.[Ni];
Properties
Chemical formula	C8H14N4NiO4
Molar mass	288.917 g·mol−1
Appearance	red solid
Density	1.698 g/cm3
Hazards
	GHS labelling:
Pictograms
Signal word	Warning
Hazard statements	H315, H317, H319, H335, H351
Precautionary statements	P201, P202, P261, P264, P271, P272, P280, P281, P302+P352, P304+P340, P305+P351+P338, P308+P313, P312, P321, P332+P313, P333+P313, P337+P313, P362, P363, P403+P233, P405, P501
	Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Nickel bis(dimethylglyoximate) is the coordination complex with the formula Ni[ONC(CH₃)C(CH₃)NOH]₂. The compound is a bright red solid. It achieved prominence for its use in the qualitative analysis of nickel.^[1]

Structure

The geometry of the nickel(II) ion is square planar.^[2] It is surrounded by two equivalents of the conjugate base (dmgH⁻) of dimethylglyoxime (dmgH₂). The pair of organic ligands are joined through hydrogen bonds to give a macrocyclic ligand. The complex is distinctively colored and insoluble leading to its use as a chelating agent in the gravimetric analysis of nickel.

The use of dimethylglyoxime as a reagent to detect nickel was reported by L. A. Chugaev in 1905.^[3]

This reaction is fairly selective thanks to the ionic radius of nickel allowing the compact stacking of Ni(dmgH)₂ in lattice, causing substantially more pronounced insolubility compared to complexes of dmg with other metals.

References

^ Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. doi:10.1016/C2009-0-30414-6. ISBN 978-0-08-037941-8.
^ Donald E. Williams; Gabriele Wohlauer; R. E. Rundle (1959). "Crystal Structures of Nickel and Palladium Dimethylglyoximes". J. Am. Chem. Soc. 81 (3): 755–756. doi:10.1021/ja01512a066.
^ Tschugaeff, Lev (1905). "Über ein neues, empfindliches Reagens auf Nickel" [About a new, sensitive reagent on nickel]. Berichte der Deutschen Chemischen Gesellschaft (in German). 38 (3): 2520–2522. doi:10.1002/cber.19050380317.

[1] Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. doi:10.1016/C2009-0-30414-6. ISBN 978-0-08-037941-8.

[2] Donald E. Williams; Gabriele Wohlauer; R. E. Rundle (1959). "Crystal Structures of Nickel and Palladium Dimethylglyoximes". J. Am. Chem. Soc. 81 (3): 755–756. doi:10.1021/ja01512a066.

[3] Tschugaeff, Lev (1905). "Über ein neues, empfindliches Reagens auf Nickel" [About a new, sensitive reagent on nickel]. Berichte der Deutschen Chemischen Gesellschaft (in German). 38 (3): 2520–2522. doi:10.1002/cber.19050380317.

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