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.
The preferred [3+2] cycloaddition before hetero-Diels–Alder reaction of 2-hydroxymethylene indanones derivatives with α-nitrosostyrene is described. New fused spiro-pyrroles-1′-oxide and spiro-1′,2′-oxazines structures are reported. The stereospecificity and regiospecificity of the cycloadditions are discussed.
First General Method for Direct Formylation of Kinetically-Generated Ketone Enolates
作者:Gregory H. Zayia
DOI:10.1021/ol990781c
日期:1999.10.1
[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.
Réaction hétéro-Diels–Alder: addition des azostyrènes sur les dérivés 2-hydroxyméthylène indanones
Hetero-Diels–Alder reactions of 2-hydroxymethylène indanone derivatives to hydrazone α-halogenocetones are described. The stereospecificity and regiospecificity of the reactions are discussed. New fused indanone-spiro-pyridazine structures are reported.