Tris hydrogen

Fluorine and sulfur (in the form of a methylthio group) are added to nucleophilic olefins with Markovnikov regwselectivity and anti stereoselectivity by di-methyl(niethylthio)sulfoninni fluoroborate and triethylamine tris(hydrogen fluoride) [777] (equation 21)... 

Electrochemical oxidation of 1,2-dihydronaphthalene or an indene in acetoni-tnle containing triethylamine tris(hydrogen fluoride) provides a mixture of tereoisomeric difluorides and vicinal fluoroacetamides [201] (equation 38)... 

Treatment of the citrate monohydrate with a 20% excess of 70% hydrogen peroxide gave a crystalline product which, after vacuum drying at 50°C corresponded approximately to the tri(hydrogen peroxidate). It decomposed violently when disturbed with a porcelain spatula. 

Moving to specific cases, [Ir(cod)(PPh3)3]BF4 (7) yields the tris hydrogen-bridged cluster shown in Eq. (5). 

The only systems which have achieved wide practical acceptance are hydrogen fluoride/ pyridine and triethylamine tris(hydrogen fluoride) combinations (Table 3). 

Triethylamine Tris(hydrogen Fluoride) (Franz s Reagent) 9... 

Formal replacement of hydrogen by fluorine takes place in the a-position of a ketone by treatment of enol acetates with triethylamine tris(hydrogen fluoride).51-55 The kinetically favored isomers are formed.51,55 Furthermore, benzylic positions bonded with an electron-withdrawing group (ketone, ester, nitrile, sulfonate) can be fluorinated electrochemically.51" 6-58 There are also various examples of the preparation of a-fluorosulfides front sulfides.51... 

Moreover, triethylamine tris(hydrogen fluoride) has been used to open epoxides in activated carbohydrate derivatives, e.g. formation of 18.08... 

Halofluorination of Alkencs with A-Halosuccinimide/Triethylaminc Tris(hydrogen Fluoride) General Procedure 96 187... 

Table 8. Halofluorination of Cycloalkenes with Triethylaminc Tris(hydrogen Fluoride) A -Halosuccinirrnde 6 1...

Halofluorinations can also be carried out with transannular oxygen participation in the case of unsaturated bicyclic epoxides. Thus, 9-oxabicyclo[6.1,0]non-4-ene (7) is attacked stereo-specifically by A -halosuccinimide and triethylamine tris(hydrogen fluoride) (or 70% HF/py-ridine), to give endo,e fo-2-fluoro-6-halo-9-oxabicyclo[3.3.1]nonane 8 (main product) and eHr/o,eWo-2-fluoro-5-halo-9-oxabicyclo[4.2.1]nonane 9.194... 

Furthermore, electrophilic anti addition of /V-(phenylselanyl)phthalimide in the presence of triethylamine tris(hydrogen fluoride) has been investigated using alkenes (Table 14)216 and alkynes.217... 

Table 14. (Phenylselanyl)fluorination at C = C Bonds by. V-(Phenylselanyl)phthalimidc/Triethylamine Tris(hydrogen Fluoride) in Dichloromethane at 25 C216...

The electrophilic anti addition of benzeneselenenyl fluoride to C = C bonds has been performed in a one-pot reaction with, /V-(phenylselanyl)phthalimide/triethylamine tris(hydrogen fluoride) using disubstituted alkynes to give a-fluoro-/T(phenylselanyl)alkenes 4.217... 

It is noticeable that neither the most commonly used less acidic triethylamine tris(hydrogen fluoride) nor the more acidic Olah s reagent (70% HF/pyridine) lead to the generation of a cyclic fluoro alcohol from 2,6-dimethylhept-5-enal (7).395... 

Vinyloxiranes, when treated with A -bromosuccinimide-triethylamine tris(hydrogen fluoride) at — 10 C in dichloromethane, are converted into the corresponding (bromofluoro-ethyl)oxiranes.43 The regioselectivity and yield of the reaction are dependent on the degree of substitution of the vinyl group. 

---