Influence of N‐Substitution in 3‐Alkyl‐3‐hydroxyisoindolin‐1‐ones on the Stereoselectivity of Brønsted Acid‐Catalyzed Synthesis of 3‐Methyleneisoindolin‐1‐ones

Abstract

AbstractA comprehensive study on the influence of N‐substitution on the stereoselective outcome of the synthesis of 3‐methyleneisoindolin‐1‐ones from 3‐alkyl‐3‐hydroxyisoindolin‐1‐ones is reported. The study was performed on an array of structurally diverse 3‐alkyl‐3‐hydroxyisoindolin‐1‐ones with tunable sizes of N‐substituents. In a methanesulfonic acid‐catalyzed reaction, substrates without N‐substituent (N−H) afforded exclusively the Z‐isomer, while an increase in their size was followed by the formation of a stereoisomeric mixture with the E‐isomer as the major component.