새로운 메탈로센 촉매의 개발과 이를 이용한 올레핀 중합
Syntheses of Novel Metallocene Complexes (Non-CGC) and their with Olefins Polymerization
- 주제(키워드) CGC , Olefin , Polymerization , LG Chem , Cyclopentadiene , Titanium
- 발행기관 아주대학교
- 지도교수 이분열 교수님
- 발행년도 2006
- 학위수여년월 2006. 2
- 학위명 석사
- 학과 및 전공 일반대학원 분자과학기술학과
- 본문언어 영어
초록/요약
1. Cyclopentadiene compounds, 2-[CR'R(OMe)]-1,3-Me2C5H3 (R, R' = 2,2'-biphenyl, 2) and 2-[CR'R(OSiMe3)]-1,3-Me2C5H3 (R, R' = 2,2'-biphenyl, 3; R = ph, R' = ph, 4; R = 2-naphthyl, R' = H, 5) are readily synthesized from 2-bromo-3-methoxy-1,3-dimethylcyclopentene (1). Reaction of the cyclopentadienes with Ti(NMe2)4 in toluene results in clean formation of the cyclopentadienyl tris(dimethylamido)titanium complexes, which are transformed to the trichloride complexes, 2-[CR'R(OMe)]-1,3-Me2C5H2}TiCl3 (R, R' = 2,2'-biphenyl, 6) and {2-[CR'R(OSiMe3)]-1,3-Me2C5H2}TiCl3 (R, R' = 2,2'-biphenyl, 7; R = ph, R' = ph, 8; R = 2-naphthyl, R' = H, 9). Attempts to form C1-bridged Cp/oxido complexes by elimination of MeCl or Me3SiCl were not successful. X-ray structures of 6, 7 and an intermediate complex {2-[Ph2C(OSiMe3)]-1,3-Me2C5H2}TiCl2(NMe2) (10) were determined.
more초록/요약
2, 3. Advantages of the CGC (constrained geometry catalyst) over the conventional biscyclopentadienyl metallocene catalysts are thermal stability, high comonomer incorporation, and high molecular weight of the obtained polymers in the ethylene/-olefin copolymerizations, which enables its use in a commercial high temperature solution process.1 Various successful modifications over the standard CGC, [Me2Si(5-Me4Cp)(NtBu)]TiCl2 have been achieved by replacement of the Me4Cp unit with other -donor ligands, but modifications on the bridge unit have not been so successful. Erker reported preparation of alkylidene (R1R2C) or vinylidene (H2C=C) bridged Cp/amido complexes but their activity for ethylene polymerization is significantly lower than the standard CGC.2 Ethylene-bridged complex, [(5-Me4Cp)CH2CH2(NtBu)]TiCl2 was reported to show much reduced incorporation of comonomer. Herein, we present a novel preparation method for ortho-phenylene-bridged Cp/sulfonamido and Cp/amido titanium complexes. Conventionally, aryl-substituted cyclopentadienyl ligands have been prepared by nucleophilic attack of aryl lithium to 2-cyclopentenone derivatives and subsequent acid-catalyzed H2O-elimination. Attempts to prepare the targeted ortho-phenylene-bridged Cp/amide ligand system by the same strategy using 2-LiC6H4N(R)Li was unsuccessful. A new synthetic route was devised by using the Suzuki-coupling. The key starting material in this route, boronic acid 1 can be prepared in 30g-scale. The boronic acid is excellent substrates for the Suzuki-coupling reaction and the cyclopentenone compounds 2 are afforded in excellent yields. The cyclopentenone compounds can be easily transformed to the cyclopentadiene compounds 3 from which various ortho-phenylene-bridged Cp/sulfonamido and Cp/amido titanium complexes are prepared. Several complexes were characterized by X-ray crystallography and some of them show higher activity, higher incorporation of 1-octene, and higher molecular weights than the standard CGC [(5-Me4Cp)CH2CH2(NtBu)]TiCl2.
more목차
CHAPTER 1. Syntheses and Structures of 1,2,3-Substituted Cyclopentadienyl Titanium(IV) Complexes
1. Introduction
2. Result and Discussion
2.1. Synthesis and Charaterizations
2.2. X-ray Crystallographic Studies
2.3. Conclusion ∙
3. Experimental Section
4. References
목차
CHAPTER 2. Phenylene-Bridged Cp/Sulfonamido Titanium Complexes for Ethylene/1-Octene Copolymerization
1. Introduction
2. Result and Discussion
2.1. Synthesis and Charaterizations
2.2. X-ray Crystallographic Studies
2.3. Polymerization Studies
3. Experimental Section
4. References
목차
CHAPTER 3. Ortho-Phenylene-Bridged Cp/Amido Titanium Complexes for Ethylene/1-Octene Copolymerization
1. Introduction
2. Result and Discussion
2.1. Synthesis and Charaterizations
2.2. X-ray Crystallographic Studies
2.3. Polymerization Studies (conducting by LG Chem. LTD)
3. Experimental Section
4. References
