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• 1401995-18-3 (2-methoxy-2-phenylethyl) methanesulfonate 
• 55163-71-8 2-methoxy-2-phenylethyl 4-methylbenzenesulfonate 

Relevant academic research and scientific papers

Mild copper-catalyzed fluorination of alkyl triflates with potassium fluoride

A chemoselective catalytic fluorination of alkyl triflates is described using potassium fluoride as a fluoride source. Excellent yields of the desired alkyl fluorides are obtained after one hour at 45°C using 2 mol% of the copper catalyst. With 10 mol% of the catalyst, full conversion can be achieved in less than 10 minutes at 45°C, and thus makes this procedure potentially suited for the preparation of 18F-labeled PET probes. As a result of the mild reaction conditions, only the substitution products are observed with no evidence of common side reactions, such as elimination. Reported is a preliminary study of the reaction scope, which demonstrates that the fluorination can be performed in the presence of a wide range of functional groups. Evidence suggests an unusual role of the [IPrCuOTf] catalyst as a phase-transfer catalyst and points to [IPrCuF] as the active fluorinating reagent (IPr=1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene).

Microwave assisted fluorofunctionalization of phenyl substituted alkenes using selectfluor

A rapid fluorofunctionalization of alkenes and diene using selectfluor has been uncovered. The olefins such as 1-phenyl ethene; 1,1-diphenylethene; (E)-1,2-diphenylethene; (E)-1,2-dinaphthylethene; 1,1,2-triphenylethene; 1,1,2,2-tetraphenylethene and 1,1,

Effect of reaction conditions on the kinetic and activation parameters for the mild introduction of fluorine into α-substituted styrenes with AccufluorTM NFTh

Kinetic studies on fluorination of α-substituted styrenes with 1-fluoro-4-hydroxy-1,4-diazoniabicyclo[2.2.2]octane bis(tetrafluoroborate) (AccufluorTM NFTh) in acetonitrile or in acetonitrile in the presence of methanol or water as nucleophiles were carried out. These reactions exhibited overall second-order kinetics and formed Markovnikov type products. The corresponding second-order rate constants for fluorination of the studied substrates in the presence of methanol at 38.8 deg C are k2 = 1.1 x 10-3 M-1 s-1 for styrene (1a), 3.3 x 10-2 M-1 s-1 for α-methylstyrene (1b) and 3.4 x 10-2 M-1 s-1 for 1,1-diphenylethene (1c). The substitution of methanol as nucleophile by water had very little effect on the rate of the process. Solvent polarity variation (Grunwald-Winstein Ybenzyl) showed a similar small effect, too, indicating negligible change in the polarity of the rate-determining transition state in comparison with the reactants. Activation enthalpies (between 62 and 80 kJ mol-1) and activation antropies (between -74 and 32 J mol-1 K-1) were determined for fluorination of α-substituted styrenes with NFTh in acetonitrile in the presence of methanol and water as nucleophiles. Hammett correlation analysis of the reaction of substituted styrenes with NFTh in MeCN MeCN-H2O and MeCN-MeOH gave reaction constants ρ+ of -1.48, -1.52 and -1.80, respectively, which support our belief in the mainly non-polar character of the rate-determining transition state of the studied reactions.

1-Fluoro-4-hydroxy-1,4-diazoniabicyclo[2.2.2]octane bis(tetrafluoroborate) as a new, effective reagent for selective fluorofunctionalisation of alkenes under mild reaction conditions

1-Fluoro-4-hydroxy-1,4-diazoniabicyclo[2.2.2]octane bis(tetrafluoroborate) Accufluor NFTh) is confirmed as a highly effective reagent for introducing a fluorine atom into organic molecules across a phenyl-substituted carbon-carbon double bond. Quantitativ

A mild, selective method for preparation of vicinal fluoro ethers using 'F-Teda-BF4

Vicinal alkoxy fluorides are efficiently formed by room temperature reaction of phenyl substituted alkenes with commercially available 1- chloromethyl-4-fluoro-1,4-diazobicyclo[2.2.2]octane bis tetrafluoroborate (Selectfluor(TM) F-Teda BF4) in

Power and structure-variable fluorinating agents. The N-fluoropyridinium salt system

The usefulness of the N-fluoropyridinium salt system as a source of fluorinating agents was examined by using substituted or unsubstituted N-fluoropyridinium triflates 1-11, N-fluoropyridinium salts possessing other counteranions 1a-d and 3a, and the counteranion-bound salts, N-fluoropyridinium-2-sulfonates 12 and 13. Electrophilic fluorinating power was found to vary remarkably according to the electronic nature of the ring substituents. This power increased as the electron density of positive nitrogen sites decreased, and this was correlated to the pKa values of the corresponding pyridines. By virtue of this variation, it was possible to fluorinate a wide range of nucleophilic substrates differing in reactivity. It is thus possible to fluorinate aromatics, carbanions, active methylene compounds, enol alkyl or silyl ethers, vinyl acetates, ketene silyl acetals, and olefins through the proper use of salts pentachloro 6 through 2,4,6-trimethyl 2, their power decreasing in this order. All the reactions could be explained on the basis of a one-electron-transfer mechanism. N-Fluoropyridinium salts showed high chemoselectivity in fluorination, the extent depending on the reactive moiety. In consideration of these Findings, selective 9α-fluorination of steroids was carried out by reacting 1 with tris(trimethylsilyl ether) 73 of a triketo steroid. Regio- or stereoselectivity in fluorination was determined by a N-fluoropyridinium salt structure. Steric bulkiness of the N-F surroundings hindered the ortho fluorination of phenols and aniline derivatives, while the capacity for hydrogen bonding on the part of the counteranions prompted this process, and the counteranion-bound salts 12 and 13 underwent this fluorination exclusively or almost so. Both bulky N-fluoropyridinium triflates 2 and 7 preferentially attacked the 6-position of the conjugated vinyl ester of a steroid from the unhindered β-direction to give a thermally unstable 6β-fluoro isomer. On the basis of these results, N-fluoropyridinium salts may be concluded to constitute a system that can serve as a source of the most ideal fluorinating agents for conducting desired selective fluorination through fluorinating capacity or structural alteration.

SYNTHESE ET PROPRIETES D'ETHERS β-MONOFLUORES

Two methods have been used for the synthesis of β-monofluorinated ethers.One is the methylation of α-fluorinated alcoholates obtained from corresponding 2-fluoroalcohols by action of NaH in T.H.F.The second method is the nucleophilic substitution of tosyl