Preparation of Thiophene-Fused and Tetrahydroquinoline-Linked Cyclopentadienyl Titanium Complexes for Ethylene/α-Olefin Copolymerization

Catalysts

Sung Hun Kim²  Ji Hae Park²  Bo Geun Song¹  Seung-Woong Yoon¹  Min Jeong Go³  Junseong Lee³ 

[1] Honam Petrochemical Company and Catalyst Research Team 5th, 24-1 Jang-Dong, Yuseong-Gu, Daejeon 305-726, Korea; E-Mails:;Department of Molecular Science and Technology, Ajou University, Suwon 443-749, Korea; E-Mails:;Department of Chemistry, Chonnam National University, 77 Yongbong-ro, Buk-gu, Gwangju 500-757, Korea; E-Mails:

关键词: titanium complex;    half-metallocene;    thiophene-fused cyclopentadienyl;    ethylene polymerization;   

DOI  :  10.3390/catal3010104

来源: mdpi

【 摘 要 】

A synthetic scheme was developed for the large-scale preparation of a dimethylthiophene-fused and tetrahydroquinaldine-linked dimethylcyclopentadienyl titanium complex (2), which is a high-performance homogeneous Ziegler catalyst. 2,3,4,5-Tetramethyl-4,5-dihydrocyclopenta[b]thiophen-6-one was prepared without chromatography purification on the 40-g scale in a laboratory setting, from which the ligand precursor for 2 was obtained in 65% yield on a 50-g scale in a one-pot without the need for chromatography purification. Metallation was achieved in a high yield (78%) through reaction of the dilithiated compound with TiCl₄. Many derivatives were prepared by employing the same synthetic scheme as applied for 2. Among them, the titanium complex prepared from 2-methyl-4,5-dimethyl-6-(2-n-butyl-2,3,4,5-tetrahydroquinolin-8-yl)-4H-cyclopenta[b]thiophene exhibited an exceptionally high activity. Under commercially relevant high-temperature polymerization conditions (160 °C), this compound showed a higher activity than 2 (126 × 10⁶ g/molTi∙h versus 72 × 10⁶ g/molTi∙h), albeit with the formation of a polymer of slightly lower molecular weight (M_w, 159,000 versus 218,000) and with a slightly lower 1-octene content (9.3 mol% versus 12 mol%).

【 授权许可】

CC BY   
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