174576-52-4Relevant academic research and scientific papers
Highly stereocontrolled synthesis of substituted propiolactones and butyrolactones from achiral lithium enolates and homochiral aldehydes
Arrastia, Iosune,Lecea, Begona,Cossio, Fernando P.
, p. 245 - 248 (1996)
Lithium enolates derived from achiral thiol esters react in a highly stereoselective fashion with homochiral aldehydes to yield the corresponding 2-oxetanones. The stereochemical outcome of the reaction corresponds to a non-chelation control, except when O-silylated mandelaldehyde is used. The propiolactones thus formed are efficiently transformed into δ-lactones via Lewis acid promoted dyotropic rearrangements.
Origins of Stereocontrol in the [2 + 2] Cycloaddition between Achiral Ketenes and Chiral α-Alkoxy Aldehydes. A Pericyclic Alternative to the Aldol Reaction
Lecea, Begona,Arrieta, Ana,Arrastia, Iosune,Cossio, Fernando P.
, p. 5216 - 5227 (2007/10/03)
Ab Initio calculations predict that the thermal [2 + 2] cycloaddition reaction between C2v-symmetric ketenes and enantiopure aldehydes takes place with high enough stereocontrol for preparative purposes. The sense of induction is predicted to be non-Felkin. It is also found that the [2 + 2] cycloaddition involving nonactivated ketenes is facilitated by using 5 M solutions of lithium perchlorate in diethyl ether. It is found that both the purely thermal and lithium-assisted [2 + 2] cycloadditions result in the same type of stereocontrol. This method constitutes a general route for the synthesis of homochiral 2-oxetanones and related compounds, thus providing a pericyclic alternative to the aldol reaction.
