Synthesis of fluorinated cyclic s-trans vinylogous acid and amide ester derivatives

A two-step procedure for the preparation of ethyl 4-amino-2-oxo-6-(trifluoromethyl)cyclohex-3-ene-1-carboxylate (enaminone) and methyl 4-hydroxy-2-oxo-6-(trifluoromethyl)cyclohex-3-ene-1-carboxylate (vinylogous acid) has been accomplished, using reactive Michael acceptors under basic condition. In addition, acyclic trifluoromethylated ester derivatives were isolated as competing by-products. The above compounds represent novel synthetically useful trifluoromethyl building blocks.