Schulz-Flory oligomerisation of ethylene by the binuclear nickel(II) complex Ni2Cl4[cis,trans,cis-1,2,3,4-tetrakis-(diphenylphosphino) cyclobutane]

The binuclear nickel(II) complex Ni2Cl4(cyclo-tetraphos)(cyclo-tetraphos =cis,trans,cis-1,2,3,4-tetrakis-(diphenylphosphino)cyclobutane) forms, upon activation with MAO, an effective and robust catalyst for the oligomerisation of ethylene to Schulz-Flory distributions of C4-C14 olefins with a mechanism where both chain transfer and chain propagation are first order in ethylene.