Fluoroethanol

Difluoroethanol [359-13-7], F2CHCH2OH, is a colorless Hquid with an alcohol-like odor mp, 28.2°C, bp, 96°C d[, 1.3084 n], 1.3320 heat of combustion, —1026 kJ/mol(—245.3 kcal/mol). It is stable to distillation and miscible with water and many organic solvents. As expected, its acidity Hes between that of 2-fluoroethanol and 2,2,2-trifluoroethanol both ia the gas phase (25) and ia 50% aqueous ethanol solution (26), where its of 1.0 x 10 is about 4.8 times smaller than that of trifluoroethanol. 

Toxic compounds that can be absorbed to a marked degree by a living plant through either its roots or its leaves have been called by British investigators systemic insecticides. Schrader (38) first found this peculiar property in certain acetals of 2-fluoroethanol and bis-(2-fluoroethoxy) methane, as well as in certain compounds of his organic phosphorus series, notably bis(dimethylamido)fluophosphate and octamethyl pyrophosphoramide. 

In this work on compounds containing the C—F link, it was obviously desirable to prepare 2-fluoroethanol, both for toxicity tests on the compound itself, and as a starting material for the production of other fluorine compounds. Swarts1 was unable to obtain 2-fluoroethanol by the action of silver fluoride or mercuric fluoride on either ethylene chlorohydrin or ethylene bromohydrin. He obtained acetaldehyde in each case. He ultimately obtained fluoroethanol in very poor yield by the indirect method of hydrolysing fluoroacetin (from bromoacetin and mercuric fluoride) for 80 hr. with dilute mineral acid. 

It seems possible to draw certain deductions from the above toxicities. It is to be noted that ethyl fluoroacetamidoacetate (XII) would almost certainly be hydrolysable in the animal body to free fluoroacetic acid, and that (XIII) and (XIV) would similarly give 2-fluoroethanol (oxidizable in vivo to fluoroacetic acid). These three compounds do, in fact, show toxicities of the same order as that of methyl fluoroacetate (or of fluoroacetic acid) (XIV) is, however, rather less toxic than might be expected. 

Oxidation of 3,6-diamino-1,2,4,5-tetrazine (198) with oxone in the presence of hydrogen peroxide yields 3,6-diamino-l,2,4,5-tetrazine-2,4-dioxide (201) (LAX-112). The same reaction with 90 % hydrogen peroxide in trifluoroacetic acid yields 3-amino-6-nitro-1,2,4,5-tetrazine-2,4-dioxide (202). Treatment of 3,6-diamino-1,2,4,5-tetrazine (198) with 2,2,2-trinitroethanol and 2,2-dinitro-2-fluoroethanol generates the Mannich condensation products (203) and (204) respectively. 

The synthesis began with conversion of D-glucose-derived compound 338 to aldehydofuranose 339. Reaction of 339 with benzylhydroxylamine in 2-fluoroethanol formed the corresponding nitrone 340 which spontaneously underwent 1,3-dipolar cycloaddition furnishing, after sequential NaI04 and NaBH4 treatment, the isoxazolidinocarbocycle 341. 

Scharge T, Emmeluth C, Haber T et al (2006) Competing hydrogen bond topologies in 2-fluoroethanol dimer. J Mol Struct 786 86-95... 

Fio. 10. Enthalpy-entropy compensations in reductions of Compound I by hydrogen donors (1) 2-fluoroethanol, (2) ethanol, (3) aliyl alcohol, (4) methanol, (6) pro-pargyl alcohol, (6) hydrogen peroxide, and (7) formic acid. Horse erythrocyte catalase in 5 m.M phosphate, pH 7 (llSb). 

Fluoroethanol, catalase and, 401, 403 Formaldehyde, catalase and, 406 Formamide, catalase and, 386,399 Formate... 

FLUOROETHANOL see FIEOOO P-FLUOROETHANOL see FIEOOO FLUOROETHENE see VPAOOO 2-FLUOROETHYL CHLOROFORMATE see FIHIOO FLUOROETHYLENE see VPAOOO FLUOROFLEX see TAI250... 

Initial reports of the use of potassium or sodium hydrogen fluoride for the fluorinating ring opening of epoxides were by KnunyanLs and co-workers.23 It was found that oxiranc was cleaved to 2-fluoroethanol in 35-40% yield when hcaLed in an autoclave with potassium hydrogen fluoride without a solvent. 

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