Kevin Blann

Ethylene trimerisation and tetramerisation catalysts with polar-substituted diphosphinoamine ligands

Chromium-based catalyst systems with polar-substituted diphosphinoamine ligands are selective for either trimerisation or tetramerisation of ethylene, depending on the position of the polar groups on the aryl rings.

N,N-Bis(diphenyl­phosphino)-1,2-dimethyl­propyl­amine

The diphenylphosphine groups in the title compound, C29H31NP2, are staggered relative to the PNP backbone. The N atom adopts an almost planar geometry with the two P atoms and the C atom attached to it, in order to accommodate the steric bulk of the phenyl groups and the alkyl group. Three C atoms of the 1,2-dimethylpropylamine group are disordered over two positions in a 9:1 ratio. The molecules pack diagonally in the unit cell across the ac plane in a head-to-tail fashion.