Reactions of cycloalkanecarboxylic acids with SF4. I. Fluorination of cyclopropanepolycarboxylic acids with SF4

Pustovit, Yu. M.; Ogojko, P. I.; Nazaretian, V.P.; Faryat'eva, L. B.

doi:10.1016/0022-1139(93)02996-r

Cited by 13 publications

(37 citation statements)

References 3 publications

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“…Aliphatic bromides 27, 28, and ester 29 were also smoothly converted into medchem- relevant products 27a−29a in 65−70% yield using sulfur tetrafluoride/water (Scheme 4). 13 We also would like to disclose the limitations of the current method. Although we could isolate the pure product 30a, the best yield was only 20% (Scheme 4).…”

Section: ■ Results and Discussionmentioning

confidence: 86%

“…Pyridine β-acetic acids are stable, and we could easily convert substrates 9−11 into trifluoromethyl cyclopropanes 9a−11a in 48−86%. Pyrazole- (12,13) and triazole-acetic acids 14, 15 were also converted into the desired products 12a−15a 12 in 61−84% yield with sulfur tetrafluoride/hydrogen fluoride. In all cases, the basic nitrogen atom prevented the use of sulfur tetrafluoride/water procedure.…”

Section: ■ Results and Discussionmentioning

confidence: 99%

“…TLC characterization was performed with precoated silica gel GF254 (0.2 mm), while column chromatography characterization was performed with silica gel (100−200 mesh). 1 H NMR spectra were recorded at 400 or 500 MHz (Varian); 19 F NMR spectra were recorded at 376 MHz (Varian); 13 C NMR spectra were recorded at 101, 126, or 151 MHz (Varian). 1 H NMR chemical shifts are calibrated using residual undeuterated solvents CHCl 3 (δ = 7.26 ppm) or DMSO (δ = 2.50 ppm).…”

Section: ■ Summarymentioning

confidence: 99%

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General and Scalable Approach to Trifluoromethyl-Substituted Cyclopropanes

et al. 2023

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CF3-cyclopropanes with aliphatic, aromatic, and even heteroaromatic substituents were prepared on a multigram scale by deoxyfluorination of cyclopropane carboxylic acids or their salts with sulfur tetrafluoride. For labile α-pyridine acetic acids, only the use of their potassium salts allowed to obtain the needed products. Derivatization of CF3-cyclopropanes into building blocks ready for direct use in medicinal chemistry was performed.

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Section: ■ Results and Discussionmentioning

confidence: 86%

Section: ■ Results and Discussionmentioning

confidence: 99%

Section: ■ Summarymentioning

confidence: 99%

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General and Scalable Approach to Trifluoromethyl-Substituted Cyclopropanes

et al. 2023

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“…The fluoroheterocyclization of dicarboxylic acids with sulfur tetrafluoride has been exten sively studied by Dmowski et al and Nazaretian et al as a predominant or side reaction observed when attempting to convert the two carboxylic acids into trifluoromethylated groups [10][11][12][13][14][15]. High yields were obtained with cycloaliphatic cis-1,2dicarboxylic acids.…”

Section: Developments In Fluorocyclization Methodologiesmentioning

confidence: 99%

Developments in Fluorocyclization Methodologies

2009

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Fluorinated organic compounds constitute a significant proportion of medicines marketed today. Since heterocycles are submotifs frequently encountered in lead compounds, the corresponding fluorinated molecules that possess coupling functional groups to increase structural complexity are sought-after building blocks, especially those with stereogenic elements. To access fluoro-heterocycles, fluorocyclizations constitute an important category of reactions that permit multiple bond construction in one pot. Reactions featuring both nucleophilic and electrophilic sources of fluorine have proved valuable for the delivery of fluorinated carbo- and heterocycles. Mechanistically, two scenarios have been validated with the fluorination occurring either prior to or after the cyclization event. Fluorinated biologically active molecules prepared by employing a fluorocyclization protocol are rare, with two notable exceptions being the synthesis of fluorogypsetin and fluorobrevianamide E. Various levels of diastereocontrol were obtained with best results observed when the cyclization step precedes the fluorination. To date, asymmetric fluorocyclizations have not been explored, with the exception of a Nazarov fluorination process. In essence, this process features a catalytic asymmetric cyclization followed by a diastereoselective fluorination. Asymmetric fluoroheterocyclizations are, however, not known. For this methodology to serve medicinal chemistry, conceptual advances are essential to access fluorinated pharmacophores with programmable stereocontrol as and when necessary.

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“…Aliphatic bromides 27, 28 and ester 29 were also smoothly converted into medchem-relevant products 27a-29a in 65-70% yield using sulfur tetrafluoride/water (Scheme 4). 13 We also would like to disclose limitations of the current method. Although, we could isolate the pure product 30a, the best yield was only 20% (Scheme 4).…”

Section: Introductionmentioning

confidence: 99%