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In 1961, a report in the Journal of the American Chemical Society detailed the synthesis of a lemon-yellow compound asssigned as the organometallic complex trans-[IrCl (CO)(PPh3) 2]. 1 The results contained in this communication were novel in a number of ways. The authors, Vaska and DiLuzio, had reduced iridium (III) to iridium (I) using just triphenylphosphine and an alcohol. They had prepared an iridium carbonyl complex without the addition of carbon monoxide. The name Vaska was to become one of the most well-known in inorganic chemistry, but it would not be due to either of these reasons. Aside from its reversible dioxygen coordination, the remarkable reactivity of Vaska’s complex toward acids, halides, and dihydrogen was quickly established, yielding discrete, stable IrIII addition products. 2

This meant that, providing one had access to an iridium chloride salt, synthetic laboratories worldwide were …