“…For example, this work has led to the discovery that low-valent metal and non-metal compounds, from across the periodic table, can reductively oligomerise CO to ethynediolate, [OC^CO] 2À , aromatic oxocarbon dianions, [C n O n ] 2À (n ¼ 2-6), and related species, under mild conditions. [4][5][6] From a historical perspective, it should be noted that alkali metals have been known to reductively oligomerise CO to salts of oxocarbon dianions since the early 19th century, though those salts have been poorly characterised. 7 In order to access well-dened s-block metal complexes of oxocarbon anions derived from CO, we have recently reported on reactions of this gas with reducing b-diketiminate coordinated magnesium(I) compounds.…”