Alkoxide-catalyzed ring expansion of 1,3-cyclobutanediones with aldehydes

1,3-Cyclobutanediones (dialkyl ketene dimer) reacted with various aromatic aldehydes to give six-membered cyclic beta-keto esters by using a catalytic amount of potassium ethoxide. Effects of alkoxide catalysts and spiro cyclic groups at the 2,4-positions of 1,3-cyclobutanediones were investigated. (C) 2020 Published by Elsevier Ltd.

Automated summary

1,3-Cyclobutanediones reacted with aromatic aldehydes to produce cyclic beta-keto esters, catalyzed by a small amount of potassium ethoxide. The effects of alkoxide catalysts and spiro cyclic groups on the 1,3-cyclobutanediones were examined.