High Diastereoface Selection in an Ester Enolate Addition to α-Alkoxy Aldehydes: Stereoselective Synthesis of α-Methylene-β-hydroxy-γ-alkoxy Esters

Article abstract of DOI:10.1021/jo00194a022

The aldol-type condensation of β-(dimethylamino)propionates 3 and 4 with a series of α-alkoxy aldehydes proceeds with unprecedented high stereoselectivity (up to 24:1) to give anti α-methylene-β-hydroxy-γ-alkoxy esters.The best results were obtained when the reaction was carried out in diethyl ether and the ester enolate was allowed to equilibrate to the thermodynamically more stable geometric isomer.