Triethylamine trihydrofluoride

In contrast to phosphorus esters, sulfur esters are usually cleaved at the carbon-oxygen bond with carbon-fluorine bond formation Cleavage of esteri nf methanesulfonic acid, p-toluenesidfonic acid, and especially trifluoromethane-sulfonic acid (tnflic acid) by fluoride ion is the most widely used method for the conversion of hydroxy compounds to fluoro derivatives Potassium fluoride, triethylamine trihydrofluoride, and tetrabutylammonium fluoride are common sources of the fluoride ion For the cleavage of a variety of alkyl mesylates and tosylates with potassium fluoride, polyethylene glycol 400 is a solvent of choice, the yields are limited by solvolysis of the leaving group by the solvent, but this phenomenon is controlled by bulky substituents, either in the sulfonic acid part or in the alcohol part of the ester [42] (equation 29)... 

The effect of ultrasound on the course of the Balz-Schiemann reaction has been studied using benzenediazonium tetrafluoroborate.263 In the presence of triethylamine trihydrofluoride in l,l,2-trichloro-l,2,2-trifluoroethane (Freon 113), fluorobenzene is formed in a 92-95% yield under 17 kHz sonication for 8 hours at 40 °C. Without ultrasound, only an 85 % yield is obtained after a reaction time of 16 hours. 

The primary amine in derivative 292 (R = H) reacts with the lactone function in the presence of triethylamine trihydrofluoride in THF to give the bicyclic 205 in 86% overall yield from the protected amine 292 (R = BOC) <2005JA15386>. 

During a recent synthesis of the antibiotic Thnicamycin, Myers and co-workers71 required mild and efficient methods for the Large scale deprotection of anome-ric TBS ethers. The first procedure [Scheme 4.48] uses triethylamine trihydrofluoride to accomplish the task in 97% yield. 

Takamatsu, S., Maruyama, T., Katayama, S., et al. (2001) Improved synthesis of 9-(2,3-dideoxy-2-fluoro-P-D-f/zrg0-pentofuranosyl)adenine (FddA) using triethylamine trihydrofluoride. Tetrahedron Lett., 42, 2321-2324. 

However, the Japanese group has noted partial cleavage of the diisopropylsi-lanediyl linkage under the acidic conditions needed for the DMTr group removal [245, 247]. To circumvent this nuisance, Kobori et al. [247] have prepared a highly cross-linked polystyrene-supported phenyldiisopropylsilyl ether linker that proved to be completely stable to detritylation and used it successfully for oligonucleotide synthesis without N-protection by O-selective phosphoramidite chemistry [246] and pyrophosphate formation on solid phase [248]. The anchor can be cleaved under almost neutral conditions by 1M TBAF-AcOH in THF (90% release after 1 h) or 0.2 M triethylamine trihydrofluoride in the presence of 0.4 M triethylamine for 4h. 

Triethylamine trihydrofluoride is less corrosive than Olah s reagent3 or anhydrous hydrogen fluoride itself, but all contact with the skin must still be avoided. The reagent has been tested for laboratory use only. The experiments should be done under an efficient hood. 

This protocol describes a deprotection scheme using aqueous methylamine and triethylamine trihydrofluoride as alternative reagents to effect nucleo-base, 2 -hydroxyl, and phosphodiester deprotection. 

Pirrung MC, Shuey SW, Lever DC, Fallon L. A convenient procedure for the deprotection of silylated nucleosides and nucleotides using triethylamine trihydrofluoride. Tetrahedron Lett 4 1345-1346, 1994. 

Westman E, Stromberg R. Removal of t-butyldimethylsilyl protection in RNA synthesis. Triethylamine trihydrofluoride is a more reliable alternative to tet-rabutylammonium fluoride. Nucleic Acids Res 22 2430-2431, 1994. 

Triethylamine trihydrofluoride is an oily liquid that does not attack borosilicate glassware. The checkers purchased it from Aldrich Chemical Company, Inc., but it is also available from Fluka Chemical Corp. and other suppliers. 

During a synthesis of the marine antitumour agent Sarcodictyin A, selective removal of a secondary and a tertiary TES ether in the presence of a primary TIPS ether was effected by treatment with 5 equivalents of triethylamine trihydrofluoride (Et3N 3HF)2 in THF at room temperature [Scheme 4.21]. ... 

The main method for the synthesis of 3-fluorodihydrofuran and tetrahydrofuran derivatives is based on cyclization reactions. Cyclization of 2-fluorobut-2-enal 17 using triethylamine trihydrofluoride gave 3-fluoro-2,5-dihydrofuran 18... 

Triethylamine trihydrofluoride Triethylamine trishydrofluoride. See Triethylamine tris (hydrogen fluoride)... 

CAS 73602-61-6 EINECS/ELINCS 277-550-5 Synonyms Hydrogen fluoride triethylamine Triethylamine trihydrofluoride Triethylamine trishydrofluoride Classification Nonaromatic amine Empirical CeHisN... 

Stuart and co-workers have reported on a novel, stable fluorinating reagent based on a cyclic hypervalent iodine(m) skeleton typically used for trifluoromethylation. Model studies for the reagent focused on the fluorination of ethyl-3-oxo-3-phenylpropanoate and showed that addition of TREAT-HF (triethylamine trihydrofluoride) is essential for the reaction to proceed. Judicious control of stoichiometry, concentration, and temperature allowed good yields of the monofluorinated compound to be obtained (Scheme 15.37). No fluorination was observed in the absence of the fluor-oindane. A range of p-ketoesters and 1,3-diketones were evaluated under the optimal conditions, and it was shown that the relative reactivity could be directly correlated with the substrate s enol content, as observed previously... 

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