Reactions of cycloalkanecarboxylic acids with SF4. IV. Fluorination of cyclohexanedicarboxylic acids with SF4

Alexeenko, Anatoliy; Nazaretian, V.P.

doi:10.1016/0022-1139(94)03135-5

Cited by 9 publications

(4 citation statements)

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“…Since the chiral centers at the positions 2 of both molecules likely remain intact, heterocycle‐bonded CF 3 group of the molecule 4a is axially oriented; in the molecule 4b it is equatorial. Corresponding 19 F NMR shifts ( δ = –67.22 ppm for 4a and –69.22 ppm for 4b ) are in line with known deshielding of the 19 F NMR signal of axial CF 3 group with respect to the signal of the equatorial one in cyclohexane derivatives , …”

Section: Resultssupporting

confidence: 79%

“…Corresponding 19 F NMR shifts (δ = -67.22 ppm for 4a and -69.22 ppm for 4b) are in line with known deshielding of the 19 F NMR signal of axial CF 3 group with respect to the signal of the equatorial one in cyclohexane derivatives. [26,27] Then we studied the removing tolylsulfanyl moiety from the position 2. Attempted radical desulfanylation of trifluoroacetates 4a,b by Bu 3 SnH in benzene led to the extensive decomposition.…”

Section: Synthesis Of Trifluoromethyl Containing Thioglycal Analogsmentioning

confidence: 99%

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Trifluoromethylated Thiopyranoid Glycals: Synthesis and Ferrier (I) Type Reactions

et al. 2018

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The synthesis of a single diastereomer of 3‐acetoxy‐2‐(trifluoromethyl)‐4‐hydroxy‐3,4‐dihydro‐2H‐thiopyran from the mixture of diastereomeric cycloadducts of p‐tolyl trifluorodithioacetate and 1‐acetoxybutadiene is described. Its acetylation and nucleophilic chlorination provides glycosylating agents with different leaving groups have been prepared. Their reactions with various O‐, S‐, N‐ and C‐nucleophiles have been studied. Depending on the conditions of the experiments, the reactions proceed as Ferrier (I) reactions affording 3‐acetoxy‐2‐(trifluoromethyl)‐6‐substituted‐3,6‐dihydro‐2H‐thiopyrans or as formal direct replacement of the leaving group in the position 4 giving 3‐acetoxy‐2‐(trifluoromethyl)‐4‐substituted‐3,4‐dihydro‐2H‐thiopyrans. The stereochemistry of the resulting products and all their precursors is discussed.

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Section: Resultssupporting

confidence: 79%

Section: Synthesis Of Trifluoromethyl Containing Thioglycal Analogsmentioning

confidence: 99%

Trifluoromethylated Thiopyranoid Glycals: Synthesis and Ferrier (I) Type Reactions

et al. 2018

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“…Pharmaceutical compounds containing two trifluoromethyl groups on arenes are well-precedented,12 however, the class of 1,2-bis(trifluoromethyl)arenes has been much less represented possibly due to the difficulty in their synthesis. Traditional methods often involved hazardous conditions (using SF 4 and HF) and lengthy procedures from trifluoromethylated building blocks 13. Our approach is more operationally simple and general for synthesizing structurally diverse 1,2-bis(trifluoromethyl)arenes.…”

Section: Resultsmentioning

confidence: 99%

Copper-mediated 1,2-bis(trifluoromethylation) of arynes

Tsui

2018

Chem. Sci.

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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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Reactions of cycloalkanecarboxylic acids with SF4. IV. Fluorination of cyclohexanedicarboxylic acids with SF4

Cited by 9 publications

References 4 publications

Trifluoromethylated Thiopyranoid Glycals: Synthesis and Ferrier (I) Type Reactions

Trifluoromethylated Thiopyranoid Glycals: Synthesis and Ferrier (I) Type Reactions

Copper-mediated 1,2-bis(trifluoromethylation) of arynes

Developments in Fluorocyclization Methodologies

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