Zinc acetate

Zinc acetate
Names
	IUPAC name Zinc acetate
	Other names Acetic acid, Zinc salt; Acetic acid, Zinc(II) salt; Dicarbomethoxyzinc; Zinc diacetate
Identifiers
CAS Number	557-34-6 (anhydrous) ; 5970-45-6 (dihydrate) ;
3D model (JSmol)	Interactive image; basic zinc acetate: Interactive image;
ChEBI	CHEBI:62984;
ChEMBL	ChEMBL1200928 ;
ChemSpider	10719 ;
ECHA InfoCard	100.008.338
EC Number	209-170-2;
E number	E650 (flavour enhancer)
PubChem CID	11192;
RTECS number	ZG8750000;
UNII	H2ZEY72PME (anhydrous) ; FM5526K07A (dihydrate) ;
UN number	3077
CompTox Dashboard (EPA)	DTXSID8038770 ;
	InChI InChI=1S/2C2H4O2.Zn/c21-2(3)4;/h21H3,(H,3,4);/q;;+2/p-2 Key: DJWUNCQRNNEAKC-UHFFFAOYSA-L ; InChI=1/2C2H4O2.Zn/c21-2(3)4;/h21H3,(H,3,4);/q;;+2/p-2 Key: DJWUNCQRNNEAKC-NUQVWONBAP;
	SMILES [Zn+2].[O-]C(=O)C.[O-]C(=O)C; basic zinc acetate: C/C1=[O]/[Zn]\35O/C(C)=[O+]\[Zn]\26\[O]=C(C)/O[Zn]4(O1)/[O]=C(C)\O[Zn](=[O]/C(C)=[O]2)(O/C(C)=[O]3)[O]456;
Properties
Chemical formula	Zn(CH3COO)2(H2O)2 (dihydrate)
Molar mass	219.50 g/mol (dihydrate); 183.48 g/mol (anhydrous)
Appearance	White solid (all forms)
Density	1.735 g/cm3 (dihydrate)
Melting point	Decomposes at 237 °C (459 °F; 510 K) (dihydrate loses water at 100 °C)
Boiling point	decomposes
Solubility in water	43 g/100 mL (20 °C, dihydrate)
Solubility	1.5 g/100 mL (methanol)
Magnetic susceptibility (χ)	−101.0·10−6 cm3/mol (+2 H2O)
Structure
Coordination geometry	octahedral (dihydrate)
Molecular shape	tetrahedral
Pharmacology
ATC code	A16AX05 (WHO)
Hazards
	GHS labelling:
Pictograms
Signal word	Danger
Hazard statements	H302, H318, H319, H410, H411
Precautionary statements	P264, P270, P273, P280, P301+P312, P305+P351+P338, P310, P330, P337+P313, P391, P501
Related compounds
Other anions	Zinc chloride
Other cations	Copper(II) acetate
Related compounds	Basic beryllium acetate
	Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). verify (what is ?) Infobox references

Zinc acetate is a salt with the formula Zn(CH₃CO₂)₂, which commonly occurs as the dihydrate Zn(CH₃CO₂)₂·2H₂O. Both the hydrate and the anhydrous forms are colorless solids that are used as dietary supplements. When used as a food additive, it has the E number E650.

Uses

Zinc acetate is a component of some medicines, e.g., lozenges for treating the common cold.^[1] Zinc acetate can also be used as a dietary supplement.^[2] As an oral daily supplement it is used to inhibit the body's absorption of copper as part of the treatment for Wilson's disease.^[3] Zinc acetate is also sold as an astringent in the form of an ointment, a topical lotion, or combined with an antibiotic such as erythromycin for the topical treatment of acne.^[4] It is commonly sold as a topical anti-itch ointment.

Zinc acetate is used as the catalyst for the industrial production of vinyl acetate from acetylene: CH₃CO₂H + C₂H₂ → CH₃CO₂CH=CH₂. Approximately 1/3 of the worlds production uses this route, which because of its environmental impact, is mainly practiced in countries with relaxed environmental regulations such as China.^[5]

Preparation

Zinc acetates are prepared by the action of acetic acid on zinc carbonate or zinc metal. Treatment of zinc nitrate with acetic anhydride is an alternative route.^[6]

Structures

In anhydrous zinc acetate the zinc is coordinated to four oxygen atoms to give a tetrahedral environment, these tetrahedral polyhedra are then interconnected by acetate ligands to give a range of polymeric structures.^[7]^[8]^[9]

In the dihydrate, zinc is octahedral, wherein both acetate groups are bidentate.^[10]^[11]

Reactions

Heating Zn(CH₃CO₂)₂ in a vacuum results in a loss of acetic anhydride, leaving a residue of "basic zinc acetate," with the formula Zn₄O(CH₃CO₂)₆. It can also be prepared by a reaction of glacial acetic acid with zinc oxide.^[12] The cluster compound has a tetrahedral structure with an oxide ligand at its center^[13] Basic zinc acetate is a common precursor to metal-organic frameworks (MOFs).

References

^ "Zinc – Fact Sheet for Health Professionals". Office of Dietary Supplements, US National Institutes of Health. February 11, 2016. Retrieved November 15, 2018.
^ Wegmüller, Rita; Tay, Fabian; Zeder, Christophe; Brnić, Marica; Hurrell, Richard F. (2014). "Zinc Absorption by Young Adults from Supplemental Zinc Citrate is Comparable with That from Zinc Gluconate and Higher than from Zinc Oxide". The Journal of Nutrition. 144 (2): 132–136. doi:10.3945/jn.113.181487. PMC 3901420. PMID 24259556.
^ "Wilson Disease". NIDDK. July 2014. Archived from the original on 2016-10-04. Retrieved November 15, 2018.
^ Schachner, L.; Eaglstein, W.; Kittles, C.; Mertz, P. (1990). "Topical erythromycin and zinc therapy for acne". Journal of the American Academy of Dermatology. 22 (2 Pt 1): 253–60. doi:10.1016/0190-9622(90)70034-f. PMID 2138176.
^ Bienewald, Frank; Leibold, Edgar; Tužina, Pavel; Roscher, Günter (2019). "Vinyl Esters". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. pp. 1–16. doi:10.1002/14356007.a27_419.pub2. ISBN 978-3-527-30385-4.
^ O. F. Wagenknecht; R. Juza (1963). "Zinc Acetate". In G. Brauer (ed.). Handbook of Preparative Inorganic Chemistry, 2nd Ed. Vol. 2pages=1087. NY, NY: Academic Press.
^ Clegg, W.; Little, I. R.; Straughan, B. P. (15 December 1986). "Monoclinic anhydrous zinc(II) acetate". Acta Crystallographica Section C. 42 (12): 1701–1703. Bibcode:1986AcCrC..42.1701C. doi:10.1107/S010827018609087X.
^ He, Hongshan (15 November 2006). "A new monoclinic polymorph of anhydrous zinc acetate". Acta Crystallographica Section E. 62 (12): m3291–m3292. doi:10.1107/S1600536806046678.
^ Capilla, A. V.; Aranda, R. A. (1979). "Anhydrous Zinc(II) Acetate (CH₃-COO)₂Zn". Crystal Structure Communications. 8: 795–797.
^ van Niekerk, J. N.; Schoening, F. R. L.; Talbot, J. H. (10 September 1953). "The crystal structure of zinc acetate dihydrate, Zn(CH₃COO)₂.2H₂O". Acta Crystallographica. 6 (8): 720–723. Bibcode:1953AcCry...6..720V. doi:10.1107/S0365110X53002015.
^ Ishioka, T.; Murata, A.; Kitagawa, Y.; Nakamura, K. T. (15 August 1997). "Zinc(II) Acetate Dihydrate". Acta Crystallographica Section C. 53 (8): 1029–1031. Bibcode:1997AcCrC..53.1029I. doi:10.1107/S0108270197004484.
^ Poshkus, Algirdas C. (June 1983). "Improved synthesis of basic zinc acetate, hexakis(.mu.-acetato)-.mu.-oxotetrazinc". Industrial & Engineering Chemistry Product Research and Development. 22 (2): 380–381. doi:10.1021/i300010a041.
^ Koyama, H.; Saito, Y. (1954). "The Crystal Structure of Zinc Oxyacetate, Zn₄O(CH₃COO)₆". Bull. Chem. Soc. Jpn. 27 (2): 112–114. doi:10.1246/bcsj.27.112.