- Selective electrochemical synthesis of 4-fluoropyridine using ET 3N-3HF
-
Pyridine was electrochemically fluorinated at platinum anode at constant voltage in acetonitrile solutions containing Et3N·3HF, as supporting electrolytes and fluorine sources. The present electrolyte solution system was mild and suitable for t
- Fang, Bin,Tao, Haisheng,Kan, Xianwen,Shang, Yongjia
-
-
Read Online
- Copper-Mediated Oxidative Fluorination of Aryl Stannanes with Fluoride
-
A regiospecific method for the oxidative fluorination of aryl stannanes using tetrabutylammonium triphenyldifluorosilicate (TBAT) and copper(II) triflate is described. This reaction is robust, uses readily available reagents, and proceeds via a stepwise protocol under mild conditions (60 °C, 3.2 h). Broad functional group tolerance, including arenes containing protic and nucleophilic groups, is demonstrated.
- Gamache, Raymond F.,Waldmann, Christopher,Murphy, Jennifer M.
-
supporting information
p. 4522 - 4525
(2016/09/28)
-
- Cu(OTf)2-mediated fluorination of aryltrifluoroborates with potassium fluoride
-
This Communication describes the Cu(OTf)2-mediated fluorination of aryltrifluoroborates with KF. The reaction proceeds under mild conditions (at 60 C over 20 h) and shows a broad substrate scope and functional group tolerance. The Cu is proposed to play two separate roles in this transformation: (1) as a mediator for the aryl-F coupling and (2) as an oxidant for accessing a proposed CuIII(aryl)(F) intermediate.
- Ye, Yingda,Schimler, Sydonie D.,Hanley, Patrick S.,Sanford, Melanie S.
-
supporting information
p. 16292 - 16295
(2013/12/04)
-
- FLUORINATION OF ORGANIC COMPOUNDS
-
Methods for fluorinating organic compounds are described herein.
- -
-
Page/Page column 25
(2012/11/06)
-
- Deoxyfluorination of phenols
-
An operationally simple ipso fluorination of phenols with a new deoxyfluorination reagent is presented.
- Tang, Pingping,Wang, Weike,Ritter, Tobias
-
supporting information; experimental part
p. 11482 - 11484
(2011/10/02)
-
- Process for preparation of substituted aromatic compound
-
A substituted aromatic compound substituted with Q is obtained by reacting a phosphazenium compound represented by formula (1) (in the formula, Q?represents an anion in a form derived by elimination of a proton from an inorganic acid, or an active hydrogen compound having an active hydrogen on an oxygen atom, a nitrogen atom or a sulfur atom; a, b, c and d, each independently, is 0 or 1, but all of them are not 0 simultaneously; and R groups represent the same or different hydrocarbon groups having 1 to 10 carbon atoms, or two Rs on each common nitrogen atom may be bonded together to form a ring structure) with a halogenated aromatic compound having halogen atoms; whereby, at least one halogen atom in the halogenated aromatic compound is substituted with Q (where, Q represents an inorganic group or an organic group in a form derived by elimination of one electron from Q?in formula (1)).
- -
-
-
- Facile preparation of aromatic fluorides by deaminative fluorination of aminoarenes using hydrogen fluoride combined with bases
-
One-pot deaminative fluorination of aminoarenes including heteroaromatics, namely, diazotization of aminoarenes followed by in situ fluoro-dediazoniation of the corresponding diazonium ions, was successfully accomplished to produce fluoroarenes in high yields by using hydrogen fluoride combined with base solutions. The diazotization stage has been found to play the most important part in yielding fluoroarenes effectively. It was greatly influenced by the composition of the HF solution and enhanced by employing appropriate amounts of bases such as pyridine under carefully controlled conditions. The fluoro-dediazoniation stage was effectively accelerated photochemically to afford fluoroarenes having polar substituents such as hydroxyl, nitro and so on in high yields.
- Yoneda,Fukuhara
-
-
- A Facile Preparation of Fluoropyridines from Aminopyridines via Diazotation and Fluorodediazoniation in HF or HF-Pyridine Solutions
-
Fluoropyridines were prepared in high yields by dizotation of aminopyridines in HF or HF-pyridine solutions, followed by dediazoniation in situ at 20-60 deg C.
- Fukuhara, Tsuyoshi,Yoneda, Norihiko,Suzuki, Akira
-
p. 435 - 438
(2007/10/02)
-
- NEW DEVELOPMENTS IN THE SYNTHESIS OF LOWER FLUORINATED PYRIDINES VIA DIAZOTIZATION-FLUORINATION OF AMINOPYRIDINES IN ANHYDROUS HYDROGEN FLUORIDE
-
The isolation and stabilization of elusive 4-fluoropyridine as the hydrochloride salt (54percent yield) from fluorodediazoniation of 4-aminopyridine in anhydrous hydrogen fluoride (AHF) is described.Unlike the low yields (0-13percent) recently reported from the chlorodediazoniation of 2,6-diaminopyridine and 3-halo-2,6-diaminopyridine, fluorodediazoniation gave high yields (49-62percent) of the corresponding 2,6-difluoropyridines.In contrast, benzene analogs, i.e. m-phenylenediamine and 4-chloro-m-phenylenediamine, form only tars under similar fluorination conditions.Vicinal aminohalopyridines, e.g. 3-amino-2-chloropyridine and 2-amino-3,5-dichloropyridine give the corresponding fluorohalopyridine in 49-89percent yield.Again, the benzene analogs, i.e. o-chloroaniline and 2,4-dichloroaniline, resist fluorination.
- Boudakian, Max M.
-
p. 497 - 506
(2007/10/02)
-
- N1s core binding energies for 2-, 3-, and 4-substituted pyridines determined by X-ray photoelectron spectroscopy. Correlations with theoretical models, substituent parameters, and gas phase basicities
-
N1s binding energies for 36 pyridines substituted at the 2-,3-, and 4-positions have been determined by X-ray photoelectron spectroscopy.The differences in BE relative to pyridine are analysed in terms of existing theoretical approaches (electrostatic, grund potential, and relaxation potential models) and compared with ΔBEC1s values calculated for analogous monosubstituted benzenes.One finds good correlations of ΔBEN1s with solution determined ?-substituent values although some substituent values deviate from the correlation probably due to solution effects which are not present in the gas phase.Correlations between ΔBEN1s and (14)N nmr chemical shifts are poor, particularly for electron withdrawing substituents.The relationship between BEN1s and gas phase basicity values (ΔG0) is good, and it appears as if the BEN1s is more sensitive to the substituent than ΔG0.MINDO/3 calculations on the methoxypyridines and their conjugate acids employing full geometry optimizations are presented and analysed in order to determine the effect of geometric relaxation on the gas phase basicity.
- Brown, R. S.,Tse, A.
-
p. 694 - 703
(2007/10/02)
-