Deoxo-Fluor® Reagent

Dialkylaminosulfur trifluorides are widely used as a safe substitute for SF4 in the replacement of oxygen by fluorine in many types of organic compounds, for example, converting alcohols to fluorides, or aldehydes and ketones to gem-difluorides. The most familiar of these reagents is DAST, while an increasingly popular one (considered safer to use than DAST) is bis(2-methoxyethyl)aminosulfur trifluoride (Deoxo-Fluor Reagent) (Scheme 7.15). 

A direct catalytic conversion of esters, lactones, and carboxylic acids to oxazolines was efficiently achieved by treatment with amino alcohols in the presence of the tetranuclear zinc cluster Zn4(0C0CF3)60 as catalyst, essential for condensation and cyclodehydration reactions. For example, the use of (5)-valinol allowed the easy synthesis of oxazolines 125 and 126 in satisfactory yields <06CC2711>. A one-pot direct preparation of various 2-substituted oxazolines (as well as benzoxazoles and oxadiazoles) was also performed from carboxylic acids and amino alcohols (or aminophenols or benzhydrazide) using Deoxo-Fluor reagent <06TL6497>. 

Deoxo-Fluor reagent is a versatile reagent for acyl fluoride generation and subsequent one-flask amide coupling. Georg and coworkers have explored the utility of this reagent for the one-flask conversion of acids to hydroxamic acids and Weinreb amides (Scheme 105) ". ... 

Treatment of polymer-supported ot-sulfonyloxy ketones with thioamides in the presence of potassium carbonate affords 1,3-thiazoles (Scheme 19), 2-Alkylbenzothiazole derivatives have been obtained by palladium-catalysed intramolecular cyclization of iV-(o-bromophenyl)thioamides (Scheme 20). p-Hydroxythioamide cyclodehydration reaction has been carried out using Deoxo-Fluor reagent, [Ai5(2-methoxyethyl)amino]sulfur trifluoride, to afford 4,5-dihydro-1,3-thiazoles (Scheme 21). ... 

Kangani, C.O. Kelley, D.E. One pot synthesis of amides or oxazolines from carboxylic acids using Deoxo-Fluor reagent. Tetrahedron Lett. 2005, 46 (51), 8917-8920. 

Deoxo-Fluor reagent) a facile synthesis of gem-difluorides. J Oig Chem 65 4830-4832. doi 10.1021/jo000020j... 

Bis-(2-methoxyethyl)aminosulfur trioxide (Deoxo-Fluor) has also been used in place of DAST. Deoxo-Fluor may have the advantage of increased thermal stability. A comparison of the two reagents for the cyclization of several peptidyl p-hydroxy amides has been reported (Table 8.13). 

Tunoori, A. R., White, J. M., Georg, G. I. A One-Flask Synthesis of Weinreb Amides from Chiral and Achiral Carboxylic Acids Using the Deoxo-Fluor Fluorinating Reagent. Org. Lett. 2000, 2, 4091-4093. 

Scheme 8.3 Reagents and conditions (a) NaBr03/ Na2S204/ Et0Ac/H20 (b) (i) Tf20, pyridine, CH2CI2 (ii) PhC02Na, toluene, 60 °C (c) Deoxo-Fluor, toluene (d) (i) N,0-bis(trimet hylsilyl)acetamide, pyrimidine, or 6-chloropurine, TMSOTf, CH3CN (ii) NH3/ MeOH.

Azides and nitriles. Carboxylic acids are activated (to form RCOF) by Deoxo-Fluor for conversion into acyl azides on reaction with NaN3. Nitriles are formed by slight variation of conditions. Usually DAST can be used but the latter reagent is thermally less stable. ... 

Bi X (2006) Deoxo-Fluor (bis(2-methoxyethyl)aminosulfur trifluoride) an advanced nucleo-phUic fluorinating reagent in oiganic synthesis. Synlett 2515-2516... 

Silhar et al. [127] investigated three alternative fluorination reagents (DAST, C4F9SO2F and Deoxo-Fluor) for the conversion of hydroxymethyl purine 87 into 90 using different bases and also pre-conversion of the hydroxyl group to a mesylate (88) or iodide (89) and treatment with AgF (Scheme 34). Ultimately, it was found that the silver fluoride displacement of the iodide was the most general route affording A7-benzyl-6-(fluoromethyl)purine 90 in isolated yields of between 72 and 84 %. 

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