Stereoselective Synthesis of 3-Substituted Ethyl (Z)-4,4,4-Trifluoro-2-formylamino-2-butenoates

Abstract

The straightforward and completely (Z)-stereoselective synthesis of various 3-substituted ethyl 4,4,4-trifluoro-2-formyl­amino-2-butenoates, useful dehydro amino acid precursors of β-trifluoromethyl substituted amino acids, is described. Key step is the Schöllkopf formylamino-methylenation protocol starting from ethyl isocyanoacetate and trifluoromethyl ketones.

Key words

organofluorine compounds - dehydro amino acids - stereoselective synthesis - isocyanoacetate - formylamino-methylenation

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CCDC 228513 contains the supplementary crystallographic data for this paper. These data can be obtained free of charge via www.ccdc.cam.ac.uk/conts/retrieving.html or from the Cambridge Crystallographic Data Centre; 12, Union Road, Cambridge CB2 1EZ, UK; fax: [phone] or [e-mail].