Synthesis of Alkyl 2-(3-acetyl-2-oxotetrahydro-3- furanyl)acrylates and alkyl 3-[2-oxodihydro- 3(2H)furanyliden]propanoates

摘要

Reaction of triphenylphosphine with unsymmetrical electrophiles such as alkyl propiolates in the presence of 2-acetyl-butyrolactone gives alkyl 2-(3-acetyl-2-oxotetrahydro-3-furanyl)acrylate and alpha-methylene-gamma-butyrolactone derivatives.There are many studies on the reaction between trivalent phosphorus nucleophiles and alkyl propiolates in the presence of OH,NH,or CH acids.In the some cases stable ylides are produced that can be isolated,but in other cases they can not be isolated and appear to occur as an intermediate on the pathway to an observed product.