Isoprene polymerization with aminopyridinato ligand supported rare-earth metal complexes. Switching of the regio- and stereoselectivityElectronic supplementary information (ESI) available: Experimental section. CCDC reference numbers 756926 (1a) and 758593 (3). For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c0cc00297f

The highly cis -1,4, trans -1,4 and 3,4-selective polymerizations of isoprene were successfully regulated by simply modifying the auxiliary ligands, metal centres and initiation groups of rare-earth metal complexes and cocatalysts. Rare-earth metal alkyl or borohydride complexes showed versatile activities and switching ( cis -1,4, trans -1,4 and 3,4) selectivities toward isoprene polymerization.