Early Metal Di(pyridyl) Pyrrolide Complexes with Second Coordination Sphere Arene-π Interactions: Ligand Binding and Ethylene Polymerization

Jessica Sampson; Gyeongshin Choi; Muhammed Naseem Akhtar; E A Jaseer; Rajesh Theravalappil; Nestor Garcia; Theodor Agapie

doi:10.1021/acsomega.9b01788

Early Metal Di(pyridyl) Pyrrolide Complexes with Second Coordination Sphere Arene-π Interactions: Ligand Binding and Ethylene Polymerization

ACS Omega. 2019 Sep 19;4(14):15879-15892. doi: 10.1021/acsomega.9b01788. eCollection 2019 Oct 1.

Authors

Jessica Sampson¹, Gyeongshin Choi¹, Muhammed Naseem Akhtar², E A Jaseer², Rajesh Theravalappil², Nestor Garcia², Theodor Agapie¹

Affiliations

¹ Division of Chemistry and Chemical Engineering, California Institute of Technology, 1200 E California Blvd., Pasadena, California 91125, United States.
² Center for Refining and Petrochemicals, King Fahd University of Petroleum and Minerals, Dhahran 31261, Saudi Arabia.

Abstract

Early metal complexes supported by hemilabile, monoanionic di(pyridyl) pyrrolide ligands substituted with mesityl and anthracenyl groups were synthesized to probe the possibility of second coordination sphere arene-π interactions with ligands with potential for allosteric control in coordination chemistry, substrate activation, and olefin polymerization. Yttrium alkyl, indolide, and amide complexes were prepared and structurally characterized; close contacts between the anthracenyl substituents and Y-bound ligands are observed in the solid state. Titanium, zirconium, and hafnium tris(dimethylamido) complexes were synthesized, and their ethylene polymerization activity was tested. In the solid state structure of one of the Ti tris(dimethylamido) complexes, coordination of Ti to only one of the pyridine donors is observed pointing to the hemilabile character of the di(pyridyl) pyrrolide ligands.