TY - JOUR
TI - A new protocol for a regioselective aldol condensation as an alternative convenient synthesis of β-ketols and α,β-unsaturated ketones
AU - Kourouli, T.
AU - Kefalas, P.
AU - Ragoussis, N.
AU - Ragoussis, V.
JO - The Journal of Organic Chemistry
PY - 2002
VL - 67
TODO - 13
SP - 4615-4618
PB - 
SN - null
TODO - 10.1021/jo0200872
TODO - Acidification, Aldehydes;  Condensation;  pH effects;  Potassium compounds;  Salts;  Saponification;  Synthesis (chemical), Ketones, alkene;  carboxylic acid derivative;  ketol;  ketone derivative;  oxoacid;  potassium hydroxide;  potassium salt, acidification;  article;  chemical reaction;  decarboxylation;  molecular interaction;  pH;  polymerization;  reaction analysis;  synthesis
TODO - A general and convenient synthesis of β-ketols and α,β-alkenones has been achieved by a Knoevenagel condensation of a β-ketoacid with an aldehyde in aqueous medium. Saponification of a β-ketoester by an aqueous KOH 10% solution gives the potassium salt of the β-ketoacid, which is condensed in situ with an aldehyde at pH 7.8-8.0, at 60 °C for 5-6 h. The intermediate β-ketocarboxylate is smoothly decarboxylated in the reaction medium, giving the β-ketol in high yield (75-90%). Acidification of the reaction mixture at pH 1 and heating at 70 °C under vigorous stirring for 6 h, leads directly to the corresponding α,β-unsaturated ketone in good yield (65-75%).
ER -