Synthesis and X-Ray Structure of a Borohydrido Metallocene of Neodymium and its Use as Pre-catalyst in Nd/Mg Dual-Component Ethylene and Isoprene Polymerisations.

Marc Visseaux (1) , Thomas Chenal (1) , Pascal Roussel (1) , André Mortreux (1)

1 UCCS - Unité de Catalyse et Chimie du Solide - UMR 8181

Cp*2Nd(BH4)(THF) (1) (Cp* = C5Me5) has been readily obtained in one step from Nd(BH4)3(THF)3 and fully characterized by 1H NMR, IR spectroscopy, and elemental analysis. Its X-Ray structure displays a neutral monomeric complex, bearing one slightly distorted terminal BH4 group. Associated to nBuEtMg, 1 affords a highly active catalyst for ethylene polymerisation, the first one prepared from a borohydrido organolanthanide pre-catalyst. In the same experimental conditions, the catalytic behaviour of 1 is similar to that of previously described Cp*2NdCl2Li(Et2O)2 (2). The 1/nBuEtMg system is not deactivated even in the presence of large excesses of THF. In contrast to its chloro homologue 2, the addition of 1 equivalent of nBuEtMg to 1 affords a catalyst for a trans-selective polymerisation of isoprene.

Mots clés: Organolanthanides; Neodymium; Borohydride; Ethylene polymerisation

Domaines: Catalyse; Polymères; Chimie de coordination

Marc Visseaux, Thomas Chenal, Pascal Roussel, André Mortreux. Synthesis and X-Ray Structure of a Borohydrido Metallocene of Neodymium and its Use as Pre-catalyst in Nd/Mg Dual-Component Ethylene and Isoprene Polymerisations.. Journal of Organometallic Chemistry, 2006, 691, pp.86-92. ⟨10.1016/j.jorganchem.2005.08.036⟩. ⟨hal-00106197⟩