505058-38-8Relevant academic research and scientific papers
The palladium-catalysed cross-coupling reaction of lithium polyfluorophenyltrimethoxyborates with 4-fluoroiodobenzene
Frohn, Hermann-Josef,Adonin, Nicolay Yu.,Bardin, Vadim V.,Starichenko, Vladimir F.
, p. 195 - 199 (2003)
Li[C6F5B(OMe)3], Li[C6 HF4B(OMe)3] (all three isomers) and Li[3,4,5-C6H2F3B(OMe)3] are the first examples of polyfluorophenyltrimethoxyborate salts which have been applied as reagents to Pd-catalysed cross-coupling reactions. A series of polyfluorinated biphenyls C6H5-n Fn-C6H4F-4′ were obtained from Li[C6H5-nFnB(OMe)3] and the model substrate 4-FC6H4I in the presence of Pd catalysts. The influence of the number and the position of fluorine atoms in the polyfluorophenyltrimethoxyborate salts on the reactivity in the coupling reaction was elucidated.
Electroanalytical features of non-uniformly doped conducting poly-3-(3,4,5-trifluorophenyl)thiophene films
Levi,Gofer,Cherkinsky,Birsa,Aurbach,Berlin
, p. 2886 - 2893 (2003)
Specially prepared, thin poly-3-(3,4,5-trifluorophenyl)thiophene, PTFPT, films were shown to possess stable p- and, most importantly, n-doping in TEABF4/sulfolane (SF) solutions. Electrodes comprising PTFPT films were studied by cyclic voltammetry (CV), potentiostatic intermittent titration (PITT), and electrochemical impedance spectroscopy (EIS). A detailed analysis of the shape of the time-dependent current transients during PITT characterization of the PTFPT electrodes has been performed. The non-uniform character of the PTFPT film doping was proved. Plots of dlogl(t)/dlog t vs. t/τd were found to be useful for understanding the response of potentiostatic transients. The Cottrell time domain during potentiostatic transients was found to be very narrow, reflecting the drastic effect of the Ohmic potential drops (mainly across the film's bulk) on the semi-infinite diffusion current transient at the shortest times, and a wide distribution of the diffusion time constants. PITT and EIS characterizations provided converging results with respect to the relevant diffusion time constants and the non-uniform character of PTFPT film doping in the SF solution. EIS measurements were found to be very useful for the determination of diffusion time constants, as they allow more effective separation of the medium frequency, Warburg response from the Ohmic and the kinetic high-frequency responses.
Synthesizing Highly Fluorinated Oligophenyls via Negishi Coupling of Fluoroarylzinc Pivalates
Engelage, Elric,Huber, Stefan M.,Stoesser, Julian
supporting information, p. 711 - 722 (2022/01/26)
Previously established general synthetic methods for the synthesis of highly fluorinated biphenyls using Suzuki Miyaura protocols require the use of organoboron compounds, which are not very stable under reactions conditions and thus need to be used in large excess. Herein, we report an improved general strategy for the synthesis of highly fluorinated biphenyls, terphenyls, and phenyl-substituted terphenyls using organozinc pivalates. The influence of several parameters was investigated: (1) in a series of monodentate phosphine ligands, XPhos showed the best performance; (2) a higher yield was obtained for substrates bearing less steric hindrance or lower amount of fluorine substitution; (3) as iodinated substrates decomposed during the reaction, brominated electrophiles were found to be superior. The presented protocol is scalable, versatile, and works with commonly used and commercially available phosphine ligands (X-Phos) and palladium sources (Pd2dba3). Also, it does not require excess nucleophile for terphenyl synthesis and only a slight excess is needed for the preparation of phenyl substituted terphenyls.
Synthesis of Polyflourinated Biphenyls; Pushing the Boundaries of Suzuki-Miyaura Cross Coupling with Electron-Poor Substrates
Bulfield, David,Huber, Stefan M.
, p. 13188 - 13203 (2017/12/26)
Polyfluorinated biphenyls are interesting and promising substrates for many different applications. Unfortunately, all current methods for the syntheses of these compounds only work for a hand full of molecules or only in very special cases. Thus, many of these compounds are still inaccessible to date. Here we report a general strategy for the synthesis of a wide range of highly fluorinated biphenyls. In our studies we investigated crucial parameters, such as different phosphine ligands and the influence of various nucleophiles and electrophiles with different degrees of fluorination. These results extend the scope of the already very versatile Suzuki-Miyaura reaction toward the synthesis of very electron-poor products, making these more readily accessible. The presented methodology is scalable and versatile without the need for elaborate phosphine ligands or Pd-precatalysts.
Canopied trans-chelating bis(N-heterocyclic carbene) ligand: Synthesis, structure and catalysis
Morgan, Brad P.,Galdamez, Gabriela A.,Gilliard Jr., Robert J.,Smith, Rhett C.
experimental part, p. 2020 - 2028 (2009/05/15)
The terphspan scaffold was employed to support a bis(N-heterocyclic carbene) ligand (1) that provides a m-terphenyl canopy over one side of its metal complexes. Single-crystal X-ray diffraction studies on a silver complex of {[Ag(1)]AgBr2}2 revealed an unusual tetranuclear silver core with a Ag-Ag bond distance of 3.0241(8) with 1 as a trans-chelating ligand (C-Ag-C = 171°). A preliminary X-ray structure of pseudo-square planar [PdCl2(1)] showed a similar binding mode of 1 (C-Pd-C = 177°). High yields were obtained in Suzuki-Miyaura coupling reactions utilizing [PdCl2(1)] as the procatalyst and the results were compared with analogous complexes of trans-spanning diphosphine (2) and diphosphinite (3) complexes. The diphosphinite complex, [PdCl2(3)], decomposes to [μ-ClPd(PPh2OH)(PPh2O)]2 at room temperature. The Royal Society of Chemistry 2009.
Iron-catalysed fluoroaromatic coupling reactions under catalytic modulation with 1,2-bis(diphenylphosphino)benzene
Hatakeyama, Takuji,Kondo, Yoshiyuki,Fujiwara, Yu-Ichi,Takaya, Hikaru,Ito, Shingo,Nakamura, Eiichi,Nakamura, Masaharu
supporting information; experimental part, p. 1216 - 1218 (2009/07/10)
A catalytic amount of 1,2-bis(diphenylphosphino)benzene (DPPBz) achieves selective cleavage of sp3-carbon-halogen bond in the iron-catalysed cross-coupling between polyfluorinated arylzinc reagents and alkyl halides, which was unachievable with
Novel Liquid Crystalline Compounds Containing Bicyclo[3.1.0]hexane Core Units
Kozhushkov, Sergei I.,Langer, Rainer,Yufit, Dmitrii S.,Howard, Judith A. K.,Schill, Heiko,Demus, Dietrich,Miyazawa, Kazutoshi,De Meijere, Armin
, p. 289 - 303 (2007/10/03)
Additions of ethyl or tert-butyl diazoacetates to 4-substituted cyclopentenes 6 and 17 under dirhodium tetraacetate/tetraoctanoate catalysis led to mixtures of tert-butyl endo,exo- and exo,exo-3-carboxyl(aryl)bicyclo[3.1.0]hexane-6-carboxylates 7 and 18 in yields of 54-90% from which exo,exo-diastereomers were isolated in yields of 39-63%. Diester exo,exo-7 was saponified and converted into diaryl diesters exo,exo-9a, b in overall yields of 42 and 46%, respectively. The esters exo,exo-18 were reduced to the corresponding hydroxymethyl derivatives, these were transformed to the iodomethyl compounds which in turn were coupled with various alkylmagnesium halides, via Li2CuCl4 catalysis, to give 3-aryl-6-alkylbicyclo[3.1.0]hexyl derivatives exo,exo-21 in overall yields of 72-83%. Fluorinated 3-(2-arylethyl)-6-pentylbicyclo[3.1.0]hexane exo,exo-32 could be prepared in five steps from 4-ethoxy-2,3-difluorobenzaldehyde 26a adopting essentially the same synthetic strategy, but in an overall yield of only 8%, and 6-(4-cyanophenyl)-3-pentylbicyclo[3.1.0]hexane exo,exo-38b was obtained by Pd(OAc)2 catalyzed cyclopropanation of 4-pentylcyclopentene 34b with (4-cyanophenyl)diazomethane 36b in 29% yield. A comparison of the liquid crystalline properties of these newly prepared compounds containing a bicyclo[3.1.0]hexane core with those of the known analogous compounds with a cyclohexane fragment shows that as a rule, a bicyclo[3.1.0]hexane moiety decreases the transition temperature, while the dielectric (Δε) and optical (Δn) anisotropies are comparable. However, the bicyclo[3.1.0]hexane unit has a poorer mesogenic potential, Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004.
A new application of (polyfluoroorgano)trifluoroborate salts: The palladium-catalysed cross-coupling reaction with substituted benzenediazonium tetrafluoroborates
Frohn, Hermann-Josef,Adonin, Nicolay Yu.,Bardin, Vadim V.,Starichenko, Vladimir F.
, p. 115 - 120 (2007/10/03)
For the first time (polyfluoroorgano)trifluoroborate salts, namely K[C6F5BF3], K[C6HF4BF3] (all three isomers), K[3,4,5-C6H2F3BF3], and K[CF2=CFBF3] were principally applied as reagents to Pd-catalysed cross-coupling reactions. A series of polyfluorinated biphenyls (polyfluorophenyl)trifluoroborate salts on the reactivity in the coupling reaction was elucidated. In addition to (polyfluorophenyl)trifluoroborate salts, the cross-coupling was expanded to a first example of a perfluoroalkenyl reagent. K[CF2=CFBF3] reacted with [4-FC6H4N2][BF4] and formed CF2=CF-C6H4F-4.
