23909-36-6Relevant academic research and scientific papers
Copolymerization behavior of unbridged indenyl metallocenes: Substituent effects on the degree of comonomer incorporation
Reybuck, Sarah E.,Meyer, Arndt,Waymouth, Robert M.
, p. 637 - 643 (2002)
The copolymerization of ethylene and 1-hexene with a variety of unbridged indenylmetallocenes was investigated and compared to unbridged bis(indenyl)zirconium dichloride and bis(cyclopentadienyl)zirconium dichloride as well as ansa-bridged rac-ethylenebis(indenyl)zirconium dichloride (EBIZrCl2). The unbridged bis(2-phenylindenyl)zirconium dichloride showed higher selectivity for the incorporation of 1-hexene than the bridged rac-ethylenebis(indenyl)zirconium dichloride and much higher 1-hexene incorporation than the unbridged bis(indenyl)zirconium dichloride and bis(cyclopentadienyl)-zirconium dichloride. Both ligands appear to be important since the 1-hexene incorporation of the mixed ligand compound (cyclopentadienyl)(2-phenylindenyl)zirconium dichloride is much lower than that of bis-(2-phenylindenyl)zirconium dichloride. For unbridged bis(indenyl)metallocenes, the nature of the substituent in the 2-position plays an important role in comonomer selectivity: bis(2-methylindenyl)zirconium dichloride and bis(2-phenylethynylindenyl)zirconium dichloride exhibit much higher 1-hexene incorporation than bis(indenyl)zirconium dichloride but lower than bis(2-phenylindenyl)zirconium dichloride.
Silver-Catalyzed Carbon Dioxide Fixation on Alkynylindenes
Chuang, Po-Yao,Okumura, Akira,Saito, Kodai,Yamada, Tohru
supporting information, (2020/11/13)
The synthesis of polycyclic indene derivatives via silver-catalyzed carbon dioxide fixation on 2-alkynylindene derivatives was achieved by nucleophilic addition of the indenyl anion to carbon dioxide involving carbon-carbon bond formation and subsequent intramolecular cyclization to the alkyne part activated by a silver catalyst. This cascade process could be applied to various substrates to obtain the corresponding products in high yields. The endo/exo selectivity of the cyclization could be controlled by the steric or electronic effect of the substituents on the substrates, and 6-endo-selective cyclization was realized to afford α-pyrone-fused indenes.
A Drastic Effect of TEMPO in Zinc-Catalyzed Stannylation of Terminal Alkynes with Hydrostannanes via Dehydrogenation and Oxidative Dehydrogenation
Kai, Yuichi,Oku, Shinya,Sakurai, Kyoko,Tani, Tomohiro,Tsuchimoto, Teruhisa
supporting information, (2019/08/21)
With a system consisting of a catalytic zinc Lewis acid, pyridine, and TEMPO in a nitrile medium, terminal alkynes coupled with HSnBu3, providing alkynylstannanes with structural diversity. The resulting alkynylstannane, without being isolated, could be directly used for Pd- and Cu-catalyzed transformations to deliver internal alkynes and more intricate tin-atom-containing molecules. Mechanistic studies indicated that TEMPOSnBu3 formed in situ from TEMPO and HSnBu3 works to stannylate the terminal alkyne in collaboration with the zinc catalyst, and that both of dehydrogenation and oxidative dehydrogenation processes are uniquely involved in a single reaction. (Figure presented.).
Functional group chemistry at the zirconocene backbone: Addition reactions to pendant alkynyl substituents
Chen, Liyi,Kehr, Gerald,Froehlich, Roland,Erker, Gerhard
, p. 73 - 83 (2008/09/20)
The nickel-catalyzed cross-coupling of 2-bromoindene with propynyl- or (phenylethynyl)magnesium bromide gives the corresponding 2-alkynyl-substituted indenyl ligands. Subsequent deprotonation and transmetallation with the bis-(tetrahydrofuran)zirconium te
Synthesis of ansa-zirconocenes based on 2-(phenylethynyl)-1H-indene. the crystal and molecular structure of the complex [μ-CH2CH 2(η5-2-PhC≡CInd)2]ZrCl2 (Ind is inden-1-yl)
Ivchenko,Nifant'ev,Mkoyan
, p. 70 - 76 (2008/02/12)
Alkynyl-substituted indene was first used as a ligand for the synthesis of transition metal complexes. ansa-Zirconocenes containing ethylene and dimethylsilylene bridges were synthesized starting from 2-(phenylethynyl)-1H- indene. The structure of the for
