2-fluoroalkanoic acids

Fluoroacetyl fluoride, 46, 6 2-Fluoroalkanoic acids from 1-alkenes, 46, 39... 

The method is general for forming wc-bromofluorides, which in turn are useful intermediates this is exemplified in their conversion to 2-fluoroalkanoic acids.2 The procedure can be applied, with minor modification, to many types of alkenes.3... 

Fluoroheptanoic acid required no more than the usual precautions accorded organic compounds, for it and its precursors have LD50>100 mg /kg in mice The relatively low toxicity of this and other 2-fluoroalkanoic acids is in contrast to the high toxicity of the w-fluoro acids F(CH2)KCOOH with n an odd number (if n = 5, LD50 =1.3 mg./kg in mice).4... 

Bromofluorination followed by the present procedure is a general way to convert 1-alkenes to 2-fluoroalkanoic acids similar results have been obtained with ethylene, propylene,... 

In contrast, reactions of esters of unsaturated acids with the sulfur tetrafluoride/hydrogen fluoride/chlorine reagent result in formal addition of C1F across the C = C bond to formchloro-fluoroalkanoic acid esters. The Markovnikov-type addition occurs in reactions with methacrylic and but-2-enoic esters to give 3-chloro-2-fluoro esters, e.g. 17, while from acrylic esters anti-Markovnikov products, 2-chloro-3-fluoro esters, e.g. 16, are formed.242... 

Moroi, Y, Yano, H., Shihata, O., Yonemitsu, T. Determination of acidity constants of per-fluoroalkanoic acids. Bull. Chem. Soc. Japan, 74 667-672 (2001). 

The reaction of "BrF generated from these reactants has been extended to terminal aliphatic alkenes to give inV. -fluorobromides.4 An example is the preparation of l-bromo-2-fluoroheptane.5 The products are convertible, as shown for the case of l-bromo-2-fluoroheptane.6 into a-fluoroalkanoic acids.7... 

Reaction of esters of hydroxyalkanoic acids with sulfur tetrafluoride, unless forcing conditions arc applied, generally results in selective replacement of the hydroxy group by fluorine to give almost equimolar mixtures of fluoroalkanoates 3 and alkoxycarbonylalkyl fluorosulfites 4 in high total yield.65... 

Abbate M, MartusceUi E, Ragosta G, Scarinzi G (1991) Tensile properties and impact behaviour of poly(D(-)3-hydroxybutyrate)/rubber blends. J Mater Sd 26 1119-1125 Abe H, Doi Y (2002) Side-chain effect of second monomer units on crystalline morphology, thermal properties, and enzymatic degradability for random copolyesters of (R)-3-hydroxybutyric add with (R)-3-hydroxyalkanoic acids. Biomacromolecules 3 133-138 Abe C, Taima Y, Nakamura Y, Doi Y (1990) New bacterial copolyester of 3-hydroxyalkanoates and 3-hydroxy-co-fluoroalkanoates produced by Pseudomonas oleovorans. Polym Commun 31 404 06... 

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