Structure and reactivity of aluminium amidinates in olefin polymerisation

Using density functional theory calculations we have studied ethylene polymerisation activity of experimentally studied aluminium amidinate homogeneous catalysts. We confirm an earlier picture for the amidinates that finite temperature effects need to be considered to rationalize catalytic activity. Static calculations do not provide any explanation for the experimentally observed activity. The tendency to form dinuclear complexes of various kinds makes this class of species rich in chemistry. The inadequacy of quantum calculations to provide accurate barriers for β-hydrogen transfer for the real experimental systems, however, renders these systems also as computationally difficult and a challenge for future studies.