233280-91-6Relevant academic research and scientific papers
One-Pot Synthesis of Fluorovinyl Acetates and β,β-Difluoro Carboxylates from a Hypervalent Iodine and Hydrogen Fluoride-Based Fluorination Reagent
Song, Zhidong,Yi, Wenbin
supporting information, p. 2727 - 2732 (2016/09/13)
A new strategy for the synthesis of fluorovinyl acetates and β,β-difluoro carboxylates using a hypervalent iodine and hydrogen fluoride-based fluorination reagent is established through a silver-catalyzed one-pot reaction involving formation of carbon-oxygen and carbon-nitrogen bonds. The generated fluoroalkenes substituted with the carbon-oxygen and carbon-nitrogen bond on the β-position have the potential to be transformed into various products which would be difficult to obtain via direct fluorination. (Figure presented.).
β,β-Difluoro analogs of α-oxo-β-phenylpropionic acid and phenylalanine
Schlosser, Manfred,Brügger, Nadia,Schmidt, Werner,Amrhein, Nikolaus
, p. 7731 - 7742 (2007/10/03)
A simple three-step procedure converted the readily accessible (2-bromo-1,1-difluoroethyl)arenes (2) into α-aryl-α,α- difluoroacetaldehydes (1). Subsequent hydrocyanation, hydrolysis, oxidation and again hydrolysis afforded β-aryl-β,β-difluoro-α- oxopropionic acids (3). Reductive amination transformed the oxoacids 3 into a separable mixture of α-hydroxyacids 11 and racemic β,β-difluoro- β-phenylalanine derivatives (4). Enantiomerically pure β,β- difluorophenylalanine (L-4a) was obtained when α,α-difluoro-α- phenylacet-aldehyde (1a) was condensed with homochiral 1-phenylethylamine, hydrogen cyanide added to the resulting imine, the diastereomeric mixture thus produced hydrolyzed to the carboxamides (15) which were found to be separable by fractional crystallization or chromatography. The pKa values of the β-aryl-β,β-difluoroalanines (4) were measured and biological profile of the latter probed. 3-(4-Chlorophenyl)-3,3-difluoro-2-oxopropionic acid (4c) proved to be a potent (Ki 27 μM) and selective inhibitor of arogenate dehydratase, a key enzyme catalyzing the last step of the phenylalanine biosynthesis.
Synthesis of γ-Fluoro-α,β-unsaturated Carboxylic Esters from Saturated α-Fluoro Aldehydes
Oldendorf, Jens,Haufe, Gu?nter
, p. 52 - 57 (2007/10/03)
γ-Fluoro-α,β-unsaturated carboxylic esters 7a, 7b and 7d and 4-fluoro-4-phenylbut-3-enoic ester (8) are obtained by two alternative pathways from 2-fluoro aldehydes 5a-d, either by Horner-Wadsworth-Emmons reaction or by Wittig reaction. The aldehydes 5a-d are prepared by Swern oxidation of the corresponding fluorohydrins 4a-d. These are available from α-olefins by bromofluorination, bromine-by-acetate replacement and subsequent hydrolysis.
