Zinc Acetate, anhydrous

Anhydrous Zinc (II) Acetate, Zn(CH₃COO)₂ is a white crystalline solid. The material is moisture-sensitive but can be dried by heating above 100° C. It is highly soluble in water as well as various polar organic solvents including ethanol. Zinc salts are inexpensive, non-toxic, and environmentally benign. Zinc Acetate is a highly favored Lewis acid in organic synthesis. It can be employed for complex regio- and enantioselective catalytic transformations. Furthermore, it has been employed in the catalytic depolymerization of polyurethane to produce monomers, which hold potential for future recycling processes.

When the anhydrous form is sublimed, it forms basic Zinc Acetate, Zn₄O(CH₃COO)₆.  This precursor is conducive for forming Zinc Oxide thin films via various deposition methods. For example, researchers from the University of New South Wales in Australia utilized anhydrous Zinc diacetate as a volatile precursor to grow Zinc Oxide thin films on crystalline copper substrates via chemical vapor deposition. Their investigation revealed that the controlled thermal decomposition of the precursor produces highly uniform and adherent metal oxide layers suitable for electronic applications such as electrodes and piezoelectric transducers.

Due to its solubility, anhydrous Zinc Acetate can also be incorporated into sol-gel syntheses.  For example, researchers from Tyndall National Institute and University College Cork, in Ireland used sol-gel methods to prepare Zinc Oxide thin films.  They prepared samples with anhydrous Zinc Acetate and dihydrate Zinc Acetate, to compare the resultant materials made by the two different starting materials.  The materials made from the anhydrous precursor had a larger crystallite size and a more porous morphology, making it more suitable for possible microelectronic and optoelectronic applications.

References

1. Mar, L. G.; Timbrell, P. Y.; Lamb, R. N. An XPS study of zinc oxide thin film growth on copper using zinc acetate as a precursor. Thin Solid Films 1993, 223, 341–347. https://doi.org/10.1016/0040-6090(93)90542-w
2. Grévy, J.-M. Zinc: Organometallic Chemistry. In Encyclopedia of Inorganic and Bioinorganic Chemistry; John Wiley & Sons, Ltd., 2011.
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3. Alam, M. M.; Varala, R.; Seema, V. Zinc Acetate in Organic Synthesis and Catalysis: A Review. Mini-Rev. Org. Chem. 2024, 21 (5), 555–587. https://doi.org/10.2174/1570193X20666230507213511
4. Boezio, A. A.; Charette, A. B. Catalytic Enantioselective Addition of Dialkylzinc to N-Diphenylphosphinoylimines. A Practical Synthesis of α-Chiral Amines. Am. Chem. Soc. 2003, 125 (7), 1692–1693. https://doi.org/10.1021/ja027673x
5. Copuroglu, M.; Koh, L. H. K.; O’Brien, S.; Crean, G. M. Comparative Characterisation of Zinc Oxide Thin Films Prepared from Zinc Acetate with or without Water of Hydration via the Sol-Gel Method. Sol-Gel Sci. Technol. 2009, 52, 432–438. https://doi.org/10.1007/s10971-009-2016-0
6. Huiwen He, Hang Su, Hanjing Yu, Kaiming Du, Fan Yang, Yifeng Zhu, Meng Ma, Yanqin Shi, Xiaojun Zhang, Si Chen, Xu Wang; Chemical Recycling of Waste Polyurethane Foams: Efficient Acidolysis under the Catalysis of Zinc Acetate. ACS Sustainable Chem. Eng. 10 April 2023; 11 (14): 5515–5523. https://doi.org/10.1021/acssuschemeng.2c07260