Synthesis of Optically Active (2-Fluoroacyl)benzenes
作者:Elke Fritz-Langhals
DOI:10.1055/s-1999-2921
日期:1999.11
Optically active (2-fluoroacyl)benzenes 1 which form a new class of compounds can be easily prepared from optically active 2-fluorocarboxylic acid chlorides 2 in high optical yield via Friedel-Crafts reaction using anhydrous iron trichloride as catalyst.
Titanium mediated asymmetric aldol reaction with α-fluoropropionimide enolates
作者:Vincent A. Brunet、David O’Hagan、Alexandra M.Z. Slawin
DOI:10.1016/j.jfluchem.2007.05.012
日期:2007.10
Aldol reaction utilising Evans N-(alpha-fluoropropyl)-2-oxazolidinones with TiCl4 have been explored. Reactions of N-(alpha-fluoropropyl)-2-oxazolidinones with aliphatic aldehydes generated (x-fluoro-p-hydroxy-aldol products with high diastereoselectivities. When (alpha R)- and (alpha S)-N-(alpha-fluoropropyl)-2-(4S)-oxazolidinones were explored as substrates they gave rise to identical aldol diastereoisomer products. Examination of the enolates formed in each case by F-19 NMR, after treatment with TiCl4, indicated that both preparations gave the same predominant enolate. This was assumed to be the E-enolate. The alpha-fluoro-beta-hydroxy-aldol products were removed from the auxiliary either by alcoholysis or reduction and converted to the corresponding alpha,beta-difluoro products by treatment with Deoxofluor (TM) (C) 2007 Elsevier B.V. All rights reserved.
Stereochemical consequences of halogen-for-halogen substitutions in the gas phase
作者:Kar Chun To、A. P. Wolf、E. P. Rack
DOI:10.1021/j150642a032
日期:1983.11
[EN] PROCESS FOR PREPARING 2-FLUOROPROPIONALDEHYDE<br/>[FR] PROCÉDÉ DE PRÉPARATION DE 2-FLUOROPROPIONALDÉHYDE
申请人:SANDOZ AG
公开号:WO2016016446A1
公开(公告)日:2016-02-04
A process comprising (i) providing a 2-fluoropropionic acid halide; (ii) hydrogenating the 2-fluoropropionic acid halide by contacting it with a heterogeneous hydrogenation catalyst in an atmosphere comprising hydrogen, obtaining a mixture comprising 2-fluoropropionic aldehyde.
Alkali metal fluorides as efficient fluorinating agents. Enantiocontroued synthesis of 2-fluoroalkyl carboxylates and 1-fluoroalkyl benzenes
作者:Eike Fritz-Langhals
DOI:10.1016/0957-4166(94)80048-0
日期:1994.6
Potassium fluoride and cesium fluoride m formamide, N-methylformamide, or acetamide are efficient fluorinatingagents. They can be used for the enantiocontrolled synthesis of 2-fluorocarboxylic acids 1a and 1-fluoroalkyl benzenes 1b from the corresponding sulfonates which are easily available in high enantiomeric purity. The scope and limitation of the synthetic method is discussed.