Metal carbonyl 18-electron complexes is sometimes catalysed by catalytic amounts of oxidants, via electron-transfer. Metal carbonyls react with reducing agents such as metallic sodium or sodium amalgam to give carbonylmetalate (or carbonylate) anions: For iron pentacarbonyl, one obtains the tetracarbonylferrate with loss of CO: Mercury can insert into the metal-metal bonds of some polynuclear metal carbonyls: The CO ligand is often susceptible to attack by nucleophiles. For example, trimethylamine oxide and bistrimethylsilylamide convert CO ligands to CO and CN, respectively. In the "Hieber base reaction", hydroxide ion attacks the CO ligand to give a metallacarboxylic acid, followed by the release of carbon
Mercury(II) hydride mercury(II) hydride, it also produces other mercury hydrides in lesser quantities, such as the mercury(I) hydrides (HgH and HgH). Unpon treatment with a Lewis base, mercury(II) hydride coverts to an adduct. Upon treatment with a standard acid, mercury(II) hydride and its adducts convert either to a mercury salt or a mercuran(2)yl derivative and elemental hydrogen. Oxidation of mercury(II) hydride gives elemental mercury. Unless cooled below , mercury(II) hydride decomposes to produce elemental mercury and hydrogen: Mercury(II) hydride was successfully synthesized and identified in 1951 by Egon Wiberg and Walter Henle, by the reaction of mercury(II) iodide and lithium tetrahydroaluminate in