Organolanthanides in catalysis

Organolanthanide-catalysed oligomerisation of 2-cycloalken-1-ones

“…Yttrium and lanthanum hydrides [(C 5 Me 5 ) 2 LnH] 2 are active catalysts for the oligomerisation of 2-cycloalken-1-ones; the average degree of oligomerisation increases with temperature.…”

“…Group 3 hydrides [(η 5 -C 5 Me 5 ) 2 LnH] 2 1 (Ln = Y 1a, La 1b) are effective catalysts for the polymerisation of α-olefins. 1,2 The presence of C-X functions (X = heteroatom) in the substrate usually leads to rapid formation of Ln-X bonds and results in deactivation of the catalyst.…”

“…1,2 The presence of C-X functions (X = heteroatom) in the substrate usually leads to rapid formation of Ln-X bonds and results in deactivation of the catalyst. Recently, however, examples have been reported on organolanthanide-catalysed polymerisation of functionalised monomers, e.g.…”

Introduction

“…Cp2Zr(R)+ + CH2C12 -Cp2Zr(R)Cl + "CH2C1+" active inactive (9) "H+" + CpaZr(R)+ » R-H (10) We have observed this type of Cl-abstraction reaction for simple cationic alkyl complexes in the absence of ethylene (eq 11). We are currently in the process of identifying the organic products of this reaction in order to determine the mechanism.…”

“…Ti/Al system (eq 3) (8) and (2) the observation that neutral lanthanide metal complexes such as (C5Me5)2Lu(CH3), which are isoelectronic with Cp2M(R)+ (neglecting f electrons), react with ethylene and propylene by insertion processes (9).…”