Abstract
Asymmetric direct aldol reaction of trifluoromethylacetaldehyde
with aldehyde using diarylprolinol as a catalyst, to afford a synthetically
useful β-trifluoromethyl-β-hydroxy aldehyde with excellent
enantioselectivity, was developed. Commercially available trifluoromethylacetaldehyde
ethyl hemiacetal was used directly as a precursor of trifluoromethylacetaldehyde
without acid pyrolysis or distillation prior to use.
Key words
asymmetric synthesis - aldol reactions - organocatalyst - diarylprolinol - trifluoromethylacetaldehyde
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