Often involving sensitive reagents and complex, unstable products, the synthesis of organometallic catalysts can be challenging. Relatively weak bonds between metal centers and coordinating groups mean that aquo and dioxygen ligands can interrupt the desired molecular structure, frequently necessitating oxygen- and water-free working conditions. Following synthesis and characterization, the optimal conditions for these catalysts must be found. Costly and unsustainable metals such as rhodium, iridium, and palladium often form the centers of catalysts, and thus their consumption must be minimized. In this work, the relevance of Easy DOE to the optimization and analysis of three iridium catalysts is discussed in two groups of variables.

The first set of conditions informs what the best working conditions of the catalysts are and helps outline its capabilities. Variables that are tested are the catalyst substituent (crown ether, methoxyethyl, or methyl), the substrate, the addition sodium or lithium salts, and the addition of water. The second set of conditions form an evaluation of environmental friendliness, nodding to Anastas and Warner’s criteria for green chemistry. Variables that are tested are the solvent (traditional solvents such as dichloromethane vs. greener choices such as acetonitrile), the pressure of hydrogen, and the sensitivity to oxygen. Easy DOE is employed to design these runs, slimming the input required to obtain meaningful data. Together, these two sets of conditions give a picture of the chemical environment that best suits the catalysts, as well as how to tune this chemistry for the greener.