Highly trans-stereospecific Isoprene Polymerization by Neodymium Borohydrido Catalysts

Fanny Bonnet (1) , Marc Visseaux (2) , Angela Pereira (1) , Denise Barbier-Baudry (1)

1 LSEO - Laboratoire de Synthèse et Electrosynthèse Organométalliques
2 UCCS - Unité de Catalyse et Chimie du Solide - UMR 8181

Highly stereospecific polymerization of isoprene was achieved using borohydrido neodymium complexes. In combination with stoichiometric amounts of dialkylmagnesium, Nd(BH4)3(THF)3 (1) and Cp*'Nd(BH4)2(THF)2 (2) (Cp*' = C5Me4nPr) afford very efficient catalysts. Activity reaches 37300 g polyisoprene/mol Nd/h. Half-lanthanidocene 2 gives rise to polyisoprene 98.5 % trans-regular, the highest content yet described for a homogeneous organometallic catalyst. NMR experiments argue for the formation of bimetallic Nd(m-BH4)Mg active species.

Domaines: Catalyse; Chimie de coordination; Polymères

Fanny Bonnet, Marc Visseaux, Angela Pereira, Denise Barbier-Baudry. Highly trans-stereospecific Isoprene Polymerization by Neodymium Borohydrido Catalysts. Macromolecules, 2005, 38, pp.3162-3169. ⟨10.1021/ma047615r⟩. ⟨hal-00106202⟩