132629-22-2Relevant academic research and scientific papers
Α, α-difluoropropionic production of esters
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Paragraph 0140-0142, (2016/10/10)
PROBLEM TO BE SOLVED: To provide a practical method of producing α,α-difluoro esters important as pharmaceutical and agricultural chemical intermediates. SOLUTION: The α,α-difluoro esters are produced by reacting α-halogeno-α-fluoro esters with salts or complexes comprising an organic base and hydrogen fluoride. Dehydrohalogenation of side reaction is controlled in the production method. Only α-fluoro-α,β-unsaturated esters of by-products are treated to be brought specifically into a high boiling-point, a boiling point difference gets remarkably large thereby between the α,α-difluoro ester of an objective product and the unsaturated ester of by-product, and a high purity product of the objective product is efficiently obtained by fractional distillation of a simple operation. The method is the practical method of producing the α,α-difluoro esters capable of solving a problem point in a prior technique. COPYRIGHT: (C)2012,JPOandINPIT
Synthetic studies for novel structure of α-nitrogenously functionalized α-fluorocarboxylic acids. Part III. Some reactions of α-bromo-α-fluorocarboxylic acids and their ethyl esters with sodium azide
Takeuchi, Yoshio,Takagi, Kumiko,Yamaba, Tomokazu,Nabetani, Manabu,Koizumi, Toru
, p. 149 - 154 (2007/10/02)
Synthesis of a novel group of α-azido-α-fluorocarboxylic acid derivatives has been attempted by azidation of the corresponding α-bromo-α-fluorocarboxylic acids or ethyl esters.Although ethyl azidofluoroacetate was obtained, over-azidation occurred very readily in most cases to afford geminally diazidated compounds.Attemped conversion of ethyl azidofluoroacetate into azidofluoroacetic acid by alkaline hydrolysis or by treatment with trimethylsilyl bromide resulted mainly in the formation of defluorinated products.It was found that, although α-fluorocarboxylates are generally considered stable, defluorination occurs under nucleophilic conditions if an additional labilizing group is present on the same carbon atom as the fluorine.
