A Fundamentally New Approach to Enantioselective Fluorination Based on Cinchona Alkaloid Derivatives/Selectfluor Combination

Shibata, Norio; Suzuki, and Emiko; Takéuchi, Yoshio

doi:10.1021/ja002732x

Cited by 225 publications

(83 citation statements)

References 14 publications

(21 reference statements)

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“…124 Cinchona alkaloids can also be used to afford enantioselectively α-fluorinated silyl enol ethers, α,α-cyanoester C-H acids, β-ketoesters, and oxindoles 125 which was applied to the synthesis of BMS-204352 (Scheme 33). 126 β-Ketoesters are also substrates for enantioselective α-fluorination utilizing cinchona-alkaloid-derived thiourea catalysts.…”

Section: Enantioselective A-fluorinationmentioning

confidence: 99%

6.06 Synthesis of Fluorides

Liang

Ritter

2014

Comprehensive Organic Synthesis II

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Section: Enantioselective A-fluorinationmentioning

confidence: 99%

6.06 Synthesis of Fluorides

Liang

Ritter

2014

Comprehensive Organic Synthesis II

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“…Selectfluor was used to prepare the N-fluoroammonium derivatives 23 a-d of cinchona alkaloids by transfer fluorination (Figure 3, Scheme 26). [66][67][68] The fluorinated reagents 23 a-d were tested in the enantioselective fluorination of the sodium enolate of 2-methyl-1-tetralone, providing the product in up to 98 % yield and with up to 50 % ee (Table 8). Higher enantioselectivities (up to 94 % ee) were later observed with modified N-fluoro cinchona alkaloids.…”

Section: Enantioselective Transformationsmentioning

confidence: 99%

“…Banks and coworkers initially voiced support for a SET mechanism to + cinchona alkaloids (see Figure 3). [66][67][68] [NÀF] explain reactions with selectfluor, [54] but later spoke of "… a substrate-dependent mechanistic continuum [S N 2(F)$fully developed SET process] …" [15] As discussed below, the difference between the two mechanisms is probably smaller than it appears, and the limits of current methods to study extremely fast reactions inhibit the definitive elucidation of the operative mechanism.…”

Section: Mechanism Of Fluorination With Selectfluor: Electron Transfementioning

confidence: 99%

Selectfluor: Mechanistic Insight and Applications

et al. 2004

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The replacement of hydrogen atoms with fluorine substituents in organic substrates is of great interest in synthetic chemistry because of the strong electronegativity of fluorine and relatively small steric footprint of fluorine atoms. Many sources of nucleophilic fluorine are available for the derivatization of organic molecules under acidic, basic, and neutral conditions. However, electrophilic fluorination has historically required molecular fluorine, whose notorious toxicity and explosive tendencies limit its application in research. The necessity for an electrophilic fluorination reagent that is safe, stable, highly reactive, and amenable to industrial production as an alternative to very hazardous molecular fluorine was the inspiration for the discovery of selectfluor. This reagent is not only one of the most reactive electrophilic fluorinating reagents available, but it is also safe, nontoxic, and easy to handle. In this Review we document the many applications of selectfluor and discuss possible mechanistic pathways for its reaction.

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“…In view of the development of more advanced recycle systems in organic syntheses, reaction in ionic liquids with heterogeneous catalysts is the best combination providing that the catalyst suspends only in ionic layer. All these properties make these systems excellent candidates for application in developing environmentally benign chemical process, and actually ionic liquids are widely diffused as greener alternatives to classical volatile organic solvents in chemical transformation [5][6][7]. Extensive research has already been carried out on incorporation of fluorine into molecules, which can lead to profound and unexpected results on biological activities and/or physical properties [5].…”

Section: Introductionmentioning

confidence: 99%