钛基茂金属催化合成1-己烯二聚体和四聚体。

Ti Group Metallocene-Catalyzed Synthesis of 1-Hexene Dimers and Tetramers.

作者信息

Kovyazin Pavel V, Bikmeeva Almira Kh, Islamov Denis N, Yanybin Vasiliy M, Tyumkina Tatyana V, Parfenova Lyudmila V

机构信息

Institute of Petrochemistry and Catalysis of Russian Academy of Sciences, Prospekt Oktyabrya, 141, 450075 Ufa, Russia.

出版信息

Molecules. 2021 May 8;26(9):2775. doi: 10.3390/molecules26092775.

DOI:10.3390/molecules26092775

PMID:34066770

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC8125888/

Abstract

1-Hexene transformations in the catalytic systems LMCl-XAlBu (L = Cp, M = Ti, Zr, Hf; L = Ind, rac-HC[THInd], M = Zr; X = H, Bu ) and [CpZrH]-ClAlR activated by MMAO-12, B(CF), or (PhC)[B(CF)] in chlorinated solvents (CHCl, CHCl, o-ClCH, ClCHCHCl) were studied. The systems [CpZrH]-MMAO-12, [CpZrH]-ClAlBu-MMAO-12, or CpZrCl-HAlBu-MMAO-12 (B(CF)) in CHCl showed the highest activity and selectivity towards the formation of vinylidene head-to-tail alkene dimers. The use of chloroform as a solvent provides further in situ dimer dimerization to give a tetramer yield of up to 89%. A study of the reaction of [CpZrH] or CpZrCl with organoaluminum compounds and MMAO-12 by NMR spectroscopy confirmed the formation of Zr,Zr-hydride clusters as key intermediates of the alkene dimerization. The probable structure of the Zr,Zr-hydride clusters and ways of their generation in the catalytic systems were analyzed using a quantum chemical approach (DFT).

摘要

研究了在氯化溶剂（CHCl₃、CH₂Cl₂、o-ClCH₂CH₂Cl、ClCH₂CH₂Cl）中，由MMAO - 12、B(C₆F₅)₃或(Ph₃C)₃[B(C₆F₅)₄]活化的催化体系LMCl - XAlBu（L = Cp，M = Ti、Zr、Hf；L = Ind，rac - HC[THInd]，M = Zr；X = H、Bu）和[CpZrH₂] - ClAlR中的1 - 己烯转化反应。[CpZrH₂] - MMAO - 12、[CpZrH₂] - ClAlBu - MMAO - 12或CpZrCl₂ - HAlBu - MMAO - 12（B(C₆F₅)₃）在CH₂Cl₂体系中对亚乙烯基头对尾烯烃二聚体的形成表现出最高的活性和选择性。使用氯仿作为溶剂可进一步使原位二聚体发生二聚反应，得到高达89%的四聚体产率。通过核磁共振光谱研究[CpZrH₂]或CpZrCl₂与有机铝化合物和MMAO - 12的反应，证实了Zr - Zr - 氢化物簇的形成是烯烃二聚反应的关键中间体。使用量子化学方法（DFT）分析了Zr - Zr - 氢化物簇的可能结构及其在催化体系中的生成方式。