Synthesis methods, structure and applications of cyanoaurate complexes with organic cation radicals and onium cations: a review

Cyanoaurate complexes represent a wide class of compounds with diverse structures and many potential practical applications, including such areas as microelectronics, nanotechnology, materials science, medicine. In contrast to metal cyanoaurates, complexes with only organic radical cations and onium/inium cations do not have a coordination polymeric structure; their crystal organization is determined only by noncovalent interactions between the structural units. The absence of well-defined coordination centers for ordering cyanoaurate anions imposes some restrictions on the ability of synthetic chemists to predict the final structure of new complexes, as well as their physicochemical properties. Nevertheless, these compounds are known to have useful conductive/dielectric, magnetic, emissive, and optical properties, which makes chemists interested in this class of gold derivatives. The present review, which includes a description of modern advances in the field of synthesis methods, the study of structural features and the possibility of practical use of di-, tetra- and dihalodicyanoaurate complexes with organic cation radicals and onium/inium cations, is based on analysis of the literature sources, most of which were published before 2022. Some later work is also presented in the review. The information presented in this paper is of a fundamental nature and may be useful for specialists in the field of inorganic and organometallic chemistry of gold. The bibliography consists of 88 references.