Organolanthanide complexes methyl methacrylate polymerization

Polymerization of methyl methacrylate ( = MMA) has been effected with the organolanthanide precatalysts [(C5Me5)2Sm( -H)]2 and (C5Me5)2LnMe(THF). Both complexes have been found to initiate the living, highly syndiospecific polymerization of methyl methacrylate, Eq. (12) [62],... 

In spite of countless applications of rare earth activation in industrial heterogeneous catalysis, most soluble complexes have long been limited to more or less stoichiometric reactions. An early example is the Kagan C-C coupling mediated by samarium(II) iodide [126]. Meanwhile, true catalytic reactions have become available. Highlights are considered the organolanthanide-catalyzed hydroamina-tion of olefins [127], the living polymerization of polar and nonpolar monomers [128], and particularly the polymerization of methyl methacrylate [129]. In the first case, lanthanocene catalysts of type 27 are employed [127]. 

Nodono, M. Tokimitsu, T. Tone, S. Makino, T. Yanagase, A. Chain transfer polymerization of methyl methacrylate initiated by organolanthanide complexes. Macromol. Chem. Phys. 2000, 201, 2282-2288. 

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