Synthesis and characterization of lithium and yttrium complexes containing tridentate pyrrolyl ligands. Single-crystal X-ray structures of {Li[C4H2N(CH2NMe2)2-2,5]}2 (1) and {[C4H2N(CH2NMe2)2-2,5]YCl2(μ-Cl) · Li(OEt2)2}2 (2) and ring-opening polymerization of ε-caprolactone

Abstract The lithiated pyrrolyl ligand, {Li[C 4 H 2 N(CH 2 NMe 2 ) 2 -2,5]} 2 ( 1 ) was synthesized and structurally characterized. Reaction of 1 with YCl 3 in the molar ratio 1:1 in diethyl ether at room temperature afforded a di-yttrium di-lithium tetranuclear complex, {[C 4 H 2 N(CH 2 NMe 2 ) 2 -2,5]YCl 2 (μ-Cl) · Li(OEt 2 ) 2 } 2 ( 2 ) in 87% yield. Compounds 1 and 2 were characterized by NMR spectroscopy and single crystal X-ray crystallography. Compound 1 shows high reactivity for the ring-opening polymerization of e-caprolactone.