Synthesis of α,β-Unsaturated Carbonyl Compounds by Titanium Tetraalkoxide-Induced Aldol Condensation under Neutral Conditions

Abstract

Aldehydes and ketones, when treated with titanium tetraalkoxides in a hydrocarbon solvent at 20-140°C, undergo aldol condensation to give a, α,β-unsaturated carbonyl compounds. To avoid Meerwein-Ponndorf-Verley type reduction of the carbonyl compounds, titantium tetra-tert-butoxide is used, if the reaction is carried out at higher temperatures. In all other cases titanium tetraisopropoxide can be successfully employed. The outlined procedure offers the possibility of performing aldol condensations under neutral conditions.