1431946-72-3

Upstream product

• 2786-07-4 2-thienyl lithium 
• 101111-41-5 1‐cyclohexylidene‐1H‐indene 
• 108-94-1 cyclohexanone 
• 95-13-6 1-indene 

Downstream Products

• 1431946-73-4 [η⁵-C₉H₆-C(cyclo-C₅H₁₀)-C₄H₃S]TiCl₃ 

Relevant academic research and scientific papers

Optimization of ethylene trimerization using catalysts based on TiCl3/half-sandwich ligands

Catalytic trimerization of ethylene using three titanium-based complexes [η5-C9H6C(R)thienyl]TiCl3 with various types of bridges (R?=?cyclo-C5H10 (C1), cyclo-C4H8 (C2) and (CH3)2 (C3)) has been successfully optimized and compared. First of all, three benzofulvene precursors, C9H6C(R), were synthesized. Then the corresponding indenyl-based ligands were obtained via the reaction of the precursors with thienyllithium. The final titanium-based catalysts display a distorted tetrahedral geometry, as expected for Ti(IV), with the ligand coordinated with a hemilabile behaviour. The structures of the compounds were confirmed on the basis of various analyses. The effect of catalyst concentration, ethylene pressure, reaction temperature and nature of the bridge as the significant factor affecting coordination and orientation of thienyl group relative to the metal centre on 1-hexene (1-C6) productivity and selectivity was investigated. Results revealed that the bulky bridge groups such as cyclo-C5H10 and cyclo-C4H8 are appropriate for ethylene trimerization due to the closer coordination of sulfur atom with Ti, especially in cationic state, and catalyst C2 with cyclo-C4H8 bridge exhibits moderate productivity equal to 785?kg 1-C6?(mol Ti)?1?h?1. According to the results, ethylene at a pressure of 10?bar, 50°C and 1.5?μmol of catalyst were selected as the best conditions for obtaining 1-C6 with high productivity and selectivity. The presence of indenyl enhances the thermal stability of the catalysts and preserves their activity in higher temperatures such as 50 and 80°C.

Highly selective trimerization of ethylene with half-sandwich cyclopentadienyl and indenyl titanium complexes bearing pendant thienyl group

A series of half-sandwich titanium complexes bearing thienyl group [Cp(Ind)-bridge-thienyl]TiCl3 (CS1-CS10) have been synthesized and show high selective ethylene trimerizaion to 1-hexene. The molecular structure of CS8 [Ind-C(cyclo-C5H10)-(5-Me-thienyl)]TiCl3 was confirmed by X-ray. No intramolecular coordination interaction between the sulfur atom on the thienyl group and the titanium center could be observed in the solid state of these complexes. After activated with MAO, the complexes can effectively catalyze ethylene trimerization. For [Cp-bridge-thienyl]TiCl 3/MAO system, the best productivity is obtained at 30 C; increasing the bulk of the substituent on the 5-position of the thienyl can improve the productivity for 1-hexene. CS6 [Cp-C(cyclo-C5H10)-(5- SiMe3-thienyl)]TiCl3 upon with MAO can make a productivity of 553 kg/(mol Ti-h) and 1-hexene selectivity of 86% at 30 C, 0.5 MPa ethylene pressure. For [Ind-bridge-thienyl] TiCl3/MAO system, catalysts have more active and more tolerant of temperature comparing to corresponding Cp complexes. For example, CS8 can make the productivity of 697 kg/(mol Ti-h) and 1-hexene selectivity of 95% at 80 C, 0.5 MPa ethylene.