Synthesis and Metal Coordination of Phosphacrown Compounds Monte L. Helm, Chemistry Department, Fort Lewis College Phoshpacrown compounds hold great potential for advances in metal-mediated catalysis and environmental remediation of toxic elements. To date, there exists no simple synthetic route to the simplest member of this family, the 9P3 ligand. The 9P3 ligand holds potential to strongly bind transition metal elements that could be potentially useful for a variety of catalytic processes or removal of heavy metals from the environment. Towards this end we have completed the first step in the synthesis of the 9P3 ligand - shown in Figure 1. Initial studies of the second step in the reaction process have shown promise for formation of the 9P3 ligand as shown in Figure 2. As a secondary aspect of this project, our lab has synthesized and isolated metal complexes of the 6P2 ligand, as shown in the crystal structure of a Rh(III) complex below. These compounds bind metals very strongly, illustrating the high affinity this family of ligands has for transition metals. Notable outcomes from this project include: synthesis of a reactive triphosphorus-dianion initial studies on the formation of the 9P3 and 18P6 crown compounds formation and characterization of new metal compounds containing the novel 6P2 ligand.