Flow synthesis of cyclobutanones via [2 + 2] cycloaddition of keteneiminium salts and ethylene gas

Abstract

A flow chemistry process for the synthesis of 2-substituted cyclobutanones, via [2 + 2] cycloaddition of keteneiminium salts and ethylene gas, is reported. Our approach uses rapid and mild reaction conditions to access a diverse array of products with good to excellent yield, alongside a good level of functional group compatibility.