Copper hydride

Copper hydride (also systematically named poly) is a pyrophoric, inorganic compound with the chemical formula (CuH)n (also written as n or CuH). It is an odourless, metastable, red solid, rarely isolated as a pure composition, that decomposes to the elements. Copper hydride is mainly produced as a reducing agent in organic synthesis and as a precursor to extremely reactive catalysts. Copper hydride (also systematically named poly) is a pyrophoric, inorganic compound with the chemical formula (CuH)n (also written as n or CuH). It is an odourless, metastable, red solid, rarely isolated as a pure composition, that decomposes to the elements. Copper hydride is mainly produced as a reducing agent in organic synthesis and as a precursor to extremely reactive catalysts. The systematic name copper hydride is the most commonly used name. It is a valid IUPAC name, being constructed according to compositional nomenclature. Copper hydride is also used generically to refer to the alloyed mixture of copper and atomic hydrogen, known as the copper-hydrogen system, of which there exists various phases. It is also used to refer to any compound containing a Cu-H bond. The oxidation state of copper in copper hydride is +1. In 1844, the French chemist Adolphe Wurtz synthesised copper hydride for the first time. This reaction consisted of the reduction of copper sulfate with hypophosphorous acid (H3PO2). In 2011, Panitat Hasin and Yiying Wu were the first to synthesise a metal hydride (copper hydride) using the technique of sonication. Copper hydride has the distinction of being the first metal hydride discovered. In 2013, it was established by Donnerer et al. that, at least up to fifty gigapascals, copper hydride cannot be synthesised by pressure alone. However, they were successful in synthesising several copper-hydrogen alloys under pressure. In copper hydride, elements adopt the Wurtzite crystal structure (polymeric), being connected by covalent bonds. Other lower metal hydrides polymerise in a similar fashion (c.f. aluminium hydride).Under certain conditions, a metastable amorphous solid forms. This solid decomposes above −60 °C (−76 °F). CuH generally behaves as a source of H–. For instance, Wurtz reported the double displacement reaction of CuH with hydrochloric acid: