Synthesis, characterization, and catalytic application of a zinc(II) complex bearing a pyrazole-based ligand

The reaction between ZnCl2 and N,N-bis[(3,5-dimethyl-1H-pyrazol-1-yl)methyl]-1-phenylethylamine (bdmppea) affords [(bdmppea)ZnCl2], whose structure has been determined by X-ray crystallography. The [(bdmppea)ZnEt2] complex in situ prepared by the reaction between [bdmppea] and ZnEt2 exhibited high activity toward the polymerization reaction of rac-lactide at room temperature. However, its activity decreased sharply with decreasing temperature. Stereospecificity of this catalyst characterized by heterotacticity (Pr) was determined by homonuclear decoupled NMR spectroscopy, which value was ∼0.58.

The reaction between ZnCl2 and N,N-bis[(3,5-dimethyl-1H-pyrazol-1-yl)methyl]-1-phenylethylamine (bdmppea) affords [(bdmppea)ZnCl2], whose structure has been determined by X-ray crystallography. The diethyl derivative [(bdmppea)ZnEt2] complex in situ prepared by the reaction between [bdmppea] and ZnEt2 exhibited high activity toward the polymerization reaction of rac-lactide with conversion of 93% at room temperature with heterotacticity (Pr) around value of 0.58.Figure optionsDownload as PowerPoint slide