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RESEARCH PRODUCT

Dinuclear chloroneodymium quinolinylcarboxylates: The molecular structures affected by water and the catalytic behavior toward isoprene polymerization

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Abstract A series of dinuclear chloroneodymium quinolinylcarboxylate compounds was synthesized and characterized. The nature and importance of metal-organic aggregations have been considered as an important factor regarding the molecular structure and catalytic performance. The neodymium center in all the title compounds exhibits the coordination numbers of 8. Cage aggregation was observed in the solid state, and the cyclic arrangement was achieved when water molecules were incorporated into the structure. Upon the activation with Al(i-Bu)3, all the title neodymium compounds form the efficient catalysts for isoprene polymerization. The catalytic activities are not strongly affected by the molecular aggregation of the precatalysts in the solid state, which indicates that the dissociation into mononuclear species takes place in the homogeneous medium. The resultant polyisoprenes exhibit high contents of the cis-1,4 fraction and high molecular weight.