Based on literature precedent 9g,15d-e and our own observations, we propose the general catalytic cycle in Figure . Initially, Cu(CH3CN)4PF6 binds to (R,R)-i Pr-DuPhos to generate a mono(chelate) species 4 followed by the monocoordination of phosphine ( ) and deprotonation to generate Cu-phosphido complex 5. The novel step in the cycle involves addition of Cu-phosphido intermediate (5) to the cyclopropene (1a). We imagined that 5 could undergo either direct nucleophilic attack 22 or insertion into the cyclopropene p-bond. Lastly, elimination of the copper catalyst regenerates 4 and releases cyclopropyl phosphine 3 to complete the catalytic cycle. To investigate our proposed mechanism, we performed a series of experiments. These experiments were performed in THF which provided a more homogeneous solution as compared to toluene. First, we obtained the rate law by variable time normalization analysis. We observed a first order dependance on the DBU concentration and a fractional order dependance on the copper catalyst concentration. In