73475-37-3Relevant academic research and scientific papers
KHMDS mediated synthesis of 9-arylfluorenes from dibenzothiophene dioxides and arylacetonitriles by tandem SNAr-decyanation-based arylation
Mylavarapu, Saketh,Yadav, Mamta,Bhanuchandra
supporting information, p. 7815 - 7819 (2018/11/21)
A straightforward KHMDS mediated synthetic route to 9-arylfluorenes from readily available starting materials has been developed. This reaction involves SNAr reactions of dioxide with arylacetonitriles, followed by decyanation reaction. The pro
Au-catalyzed biaryl coupling to generate 5- to 9-membered rings: Turnover-limiting reductive elimination versus π-complexation
Corrie, Tom J. A.,Ball, Liam T.,Russell, Christopher A.,Lloyd-Jones, Guy C.
, p. 245 - 254 (2017/05/29)
The intramolecular gold-catalyzed arylation of arenes by aryl-trimethylsilanes has been investigated from both mechanistic and preparative aspects. The reaction generates 5- to 9-membered rings, and of the 44 examples studied, 10 include a heteroatom (N, O). Tethering of the arene to the arylsilane provides not only a tool to probe the impact of the conformational flexibility of Ar-Au-Ar intermediates, via systematic modulation of the length of aryl-aryl linkage, but also the ability to arylate neutral and electron-poor arenes-substrates that do not react at all in the intermolecular process. Rendering the arylation intramolecular also results in phenomenologically simpler reaction kinetics, and overall these features have facilitated a detailed study of linear free energy relationships, kinetic isotope effects, and the first quantitative experimental data on the effects of aryl electron demand and conformational freedom on the rate of reductive elimination from diaryl-gold(III) species. The turnover-limiting step for the formation of a series of fluorene derivatives is sensitive to the reactivity of the arene and changes from reductive elimination to π-complexation for arenes bearing strongly electron-withdrawing substituents (σ > 0.43). Reductive elimination is accelerated by electron-donating substituents (ρ = -2.0) on one or both rings, with the individual σ-values being additive in nature. Longer and more flexible tethers between the two aryl rings result in faster reductive elimination from Ar-Au(X)-Ar and lead to the π-complexation of the arene by Ar-AuX2 becoming the turnover-limiting step.
Au-Catalyzed Biaryl Coupling to Generate 5- To 9-Membered Rings: Turnover-Limiting Reductive Elimination versus ?-Complexation
Ball, Liam T.,Corrie, Tom J. A.,Lloyd-Jones, Guy C.,Russell, Christopher A.
, p. 245 - 254 (2021/09/04)
The intramolecular gold-catalyzed arylation of arenes by aryl-trimethylsilanes has been investigated from both mechanistic and preparative aspects. The reaction generates 5- to 9-membered rings, and of the 44 examples studied, 10 include a heteroatom (N, O). Tethering of the arene to the arylsilane provides not only a tool to probe the impact of the conformational flexibility of Ar-Au-Ar intermediates, via systematic modulation of the length of aryl-aryl linkage, but also the ability to arylate neutral and electron-poor arenes - substrates that do not react at all in the intermolecular process. Rendering the arylation intramolecular also results in phenomenologically simpler reaction kinetics, and overall these features have facilitated a detailed study of linear free energy relationships, kinetic isotope effects, and the first quantitative experimental data on the effects of aryl electron demand and conformational freedom on the rate of reductive elimination from diaryl-gold(III) species. The turnover-limiting step for the formation of a series of fluorene derivatives is sensitive to the reactivity of the arene and changes from reductive elimination to ?-complexation for arenes bearing strongly electron-withdrawing substituents (σ > 0.43). Reductive elimination is accelerated by electron-donating substituents (ρ = -2.0) on one or both rings, with the individual σ-values being additive in nature. Longer and more flexible tethers between the two aryl rings result in faster reductive elimination from Ar-Au(X)-Ar and lead to the ?-complexation of the arene by Ar-AuX2 becoming the turnover-limiting step.
A simple and efficient synthesis of 9-arylfluorenes via metal-free reductive coupling of arylboronic acids and N-tosylhydrazones in situ
Shen, Xu,Gu, Ningning,Liu, Ping,Ma, Xiaowei,Xie, Jianwei,Liu, Yan,He, Lin,Dai, Bin
, p. 63726 - 63731 (2015/08/11)
A general, yet efficient synthesis method of 9-arylfluorenes via metal-free reductive coupling of N-tosylhydrazones and arylboronic acids has been developed. This methodology is realized by a one-pot protocol in two steps involving the preparation of N-tosylhydrazones by reacting tosylhydrazide with 9-fluorenone derivatives, followed by the reductive coupling of arylboronic acid in the presence of potassium carbonate to afford various 9-arylfluorenes analogues in moderate to excellent yields. Importantly, the catalytic system presented here enables the use of easily accessible starting materials and can be employed on a wide variety of substrates with good functional group tolerance. This protocol could also be particularly useful for the synthesis of 9-fluorenyl-substituted carbazolyl compounds.
Direct C-H bond arylation of fluorenes with aryl chlorides catalyzed by N-heterocyclic carbene-palladium(ii)-1-methylimidazole complex and further transformation of the products in a one-pot procedure
Ji, Ya-Yun,Lu, Li-Li,Shi, Yu-Chun,Shao, Li-Xiong
, p. 8488 - 8498 (2014/12/10)
We report here the NHC-Pd(ii)-Im complex 1-catalyzed direct C-H bond functionalization of the C9 position of fluorenes with aryl chlorides and further transformation of the resulting products in a one-pot procedure. Under the optimal conditions, arylated fluorenes can be obtained in moderate to almost quantitative yields using various activated and unactivated (hetero)aryl chlorides as the arylating reagents. Furthermore, if the mixture from the arylation reaction is exposed to air, the C9-oxidized products can be obtained in acceptable to good yields in a one-pot procedure. In addition, alkyl groups can also be efficiently introduced to the above mixture from the arylation reaction, producing further C9-alkylated products in good to almost quantitative yields in a one-pot procedure, thus providing an expedient, inexpensive and practical strategy for the mono- and di-functionalization of fluorenes. This journal is
Highly efficient synthesis of polysubstituted fluorene via iron-catalyzed intramolecular Friedel-Crafts alkylation of biaryl alcohols
Sarkar, Soumen,Maiti, Sukhendu,Bera, Krishnendu,Jalal, Swapnadeep,Jana, Umasish
, p. 5544 - 5547 (2012/11/07)
An efficient and mild Fe(III)-catalyzed intramolecular Friedel-Crafts alkylation of biaryl methanol derivatives has been developed to achieve the substituted fluorene derivatives. The present reaction provides an excellent alternative to published methods
Unverbrueckte fluorenylkomplexe des typs (C5H5)(9-R-C13H8)ZrCl2 (R = Me3Si, Alkyl, Aryl): Synthese, charakterisierung und anwendung als katalysatoren bei der homogenen olefinpolymerisation
Schmid, Michael A.,Alt, Helmut G.,Milius, Wolfgang
, p. 15 - 22 (2007/10/03)
The reaction of various 9-substituted fluorene compounds (9-R-C13H9) (R = Me3Si, alkyl, aryl) (1a-i) with butyllithium followed by treatment with (C5H5)ZrCl3 leads to unbridged fluorenyl complexes of the type (C5H5)(9-R-C13H8)ZrCl2 (2a-i). In combination with methylaluminoxane, complexes 2a-i show a high catalytic activity as homogeneous ethylene polymerization catalysts. Compounds 2c (R = iPr), 2d (R = cyclohexyl), and 2e (R = tBu) were characterized by X-ray structure analyses.
The Reduction of Fluorine-containing Triarylmethanols by Formic Acid
Andrews, Adrian F.,Mackie, Raymond K.,Walton, John C.
, p. 96 - 102 (2007/10/02)
Triarylmethanols containing one or more fluorine substituents in the para-positions are converted by 90 percent formic acid into a mixture of the fluorine-containing triarylmethane, and a second component in which one fluorine has been replaced by a hydro
