Unknown

Dataset Information

0

Preparation of Pincer Hafnium Complexes for Olefin Polymerization.


ABSTRACT: Pincer-type [Cnaphthyl, Npyridine, Namido]HfMe2 complex is a flagship among the post-metallocene catalysts. In this work, various pincer-type Hf-complexes were prepared for olefin polymerization. Pincer-type [Namido, Npyridine, Namido]HfMe2 complexes were prepared by reacting in situ generated HfMe4 with the corresponding ligand precursors, and the structure of a complex bearing 2,6-Et2C6H3Namido moieties was confirmed by X-ray crystallography. When the ligand precursors of [(CH3)R2Si-C5H3N-C(H)PhN(H)Ar (R = Me or Ph, Ar = 2,6-diisopropylphenyl) were treated with in situ generated HfMe4, pincer-type [Csilylmethyl, Npyridine, Namido]HfMe2 complexes were afforded by formation of Hf-CH2Si bond. Pincer-type [Cnaphthyl, Sthiophene, Namido]HfMe2 complex, where the pyridine moiety in the flagship catalyst was replaced with a thiophene unit, was not generated when the corresponding ligand precursor was treated with HfMe4. Instead, the [Sthiophene, Namido]HfMe3-type complex was obtained with no formation of the Hf-Cnaphthyl bond. A series of pincer-type [Cnaphthyl, Npyridine, Nalkylamido]HfMe2 complexes was prepared where the arylamido moiety in the flagship catalyst was replaced with alkylamido moieties (alkyl = iPr, cyclohexyl, tBu, adamantyl). Structures of the complexes bearing isopropylamido and adamantylamido moieties were confirmed by X-ray crystallography. Most of the complexes cleanly generated the desired ion-pair complexes when treated with an equivalent amount of [(C18H37)2N(H)Me]+[B(C6F5)4]-, which showed negligible activity in olefin polymerization. Some complexes bearing bulky substituents showed moderate activities, even though the desired ion-pair complexes were not cleanly afforded.

SUBMITTER: Kwon SJ 

PROVIDER: S-EPMC6540127 | biostudies-literature | 2019 Apr

REPOSITORIES: biostudies-literature

altmetric image

Publications

Preparation of Pincer Hafnium Complexes for Olefin Polymerization.

Kwon Su Jin SJ   Baek Jun Won JW   Lee Hyun Ju HJ   Kim Tae Jin TJ   Ryu Ji Yeon JY   Lee Junseong J   Shin Eun Ji EJ   Lee Ki Soo KS   Lee Bun Yeoul BY  

Molecules (Basel, Switzerland) 20190429 9


Pincer-type [C<sup>naphthyl</sup>, N<sup>pyridine</sup>, N<sup>amido</sup>]HfMe<sub>2</sub> complex is a flagship among the post-metallocene catalysts. In this work, various pincer-type Hf-complexes were prepared for olefin polymerization. Pincer-type [N<sup>amido</sup>, N<sup>pyridine</sup>, N<sup>amido</sup>]HfMe<sub>2</sub> complexes were prepared by reacting in situ generated HfMe<sub>4</sub> with the corresponding ligand precursors, and the structure of a complex bearing 2,6-Et<sub>2</sub>C  ...[more]

Similar Datasets

| S-EPMC6680767 | biostudies-literature
| S-EPMC7285347 | biostudies-literature
| S-EPMC8400551 | biostudies-literature
| S-EPMC8126221 | biostudies-literature
| S-EPMC7561051 | biostudies-literature
| S-EPMC9256636 | biostudies-literature
| S-EPMC6042142 | biostudies-literature
| S-EPMC5521993 | biostudies-literature
| S-EPMC6856677 | biostudies-literature
| S-EPMC8162749 | biostudies-literature