Synthesis of a diniobium tetraphosphorus complex by a 2(3-1) process

Dimer [P2Nb(ODipp)(3)](2) (Dipp = 2,6-(Pr2C6H3)-Pr-i) has been obtained via a novel 2(3-1)'' synthetic strategy. The mononuclear diphosphorus complex P2Nb(ODipp)(3) targeted for generation by formal P- abstraction from previously reported [Na(THF)(3)][P3Nb(ODipp)(3)] ostensibly undergoes irreversible dimerization to form the [P2Nb(ODipp)(3)](2) complex, and is alternatively trapped reversibly by 1,3-cyclohexadiene with in situ formation of C6H8P2Nb(ODipp)(3). The molecular structure of [P2Nb(ODipp)(3)](2) has been determined by X-ray crystallography. Computational studies provide further insights into the bonding and reactivity of P2Nb(ODipp)(3), [P2Nb(ODipp)(3)](2), and C6H8P2Nb(ODipp)(3).