First General Method for Direct Formylation of Kinetically-Generated Ketone Enolates
摘要:
[GRAPHICS]2,2,2-Trifluoroethyl formate reacts rapidly at -78 degrees C with preformed ketone enolates to give alpha-formyl ketones in good yields. In addition, this procedure allows for complete reversal of the regioselectivity of the classical Claisen reaction and provides a superior method for the alpha'-formylation of alpha,beta-unsaturated ketones.