Indium complexes incorporating bidentate substituted pyrrole ligand: Synthesis, characterization, and ring-opening polymerization of ε-caprolactone

Abstract

The reactions of InCl 3 with two and three equivalents of lithium (2-dimethylaminomethyl)pyrrolate ( 1) in diethyl ether solutions afford In[C 4H 3N(CH 2NMe 2)] 2Cl ( 2) and In[C 4H 3N(CH 2NMe 2)] 3 ( 3) in 92% and 50% yield, respectively. Subsequent reactions of 2 with MeLi and Li(C CPh) yield In[C 4H 3N(CH 2NMe 2)] 2Me ( 4) and In[C 4H 3N(CH 2NMe 2)] 2(C CPh) ( 5), respectively. All compounds were confirmed by 1H and 13C NMR spectroscopy and compounds 3, 4, and 5 were further characterized by single-crystal X-ray crystallography. Compounds 2, 3, and 4 showed moderate catalytic activity toward the ring-opening polymerization of ε-caprolactone.