A Planar Ti2P2 Core Assembled by Reductive Decarbonylation of −O−C≡P and P−P Radical Coupling

The first structural elucidation of the first group 4 transition metal P2 complex, namely [(nacnac)Ti(OAr)]2(μ2:η2,η2-P2) (1), is reported. Complex 1 is formed via reductive decarbonylation of the phosphaethynolate ion -[OCP], which serves as a P atom source. The rhombic Ti2P2 core is essentially planar with short bond lengths suggesting some degree of multiple bonding character between the Ti-P and P-P sites. Also observed in 1 was the rather downfield shifted 31P NMR spectroscopic signal, appearing as a broadened resonance (Δν1/2 ~ 4034 Hz) at 907 ppm. Computational studies of 1 provide an understanding of the Ti2P2 core as well as the origin of the highly downfield 31P NMR spectroscopic signal.