Enamine-assisted facile generation of trifluoroacetaldehyde from trifluoroacetaldehyde ethyl hemiacetal and its carbon–carbon bond forming reaction leading to β-hydroxy-β-trifluoromethyl ketones

Trifluoroacetaldehyde ethyl hemiacetal 1 readily reacts with various enamines 2 in hexane at room temperature for 1 h to give the corresponding β-hydroxy-β-trifluoromethyl ketones in good yields.