1,5,7‐Triazabicyclo[4.4.0]dec‐5‐ene (TBD): An Organocatalyst for Rapid Access to 3‐Hydroxyisoindolin‐1‐ones

Abstract The readily available organocatalyst 1,5,7‐triazabicyclo[4.4.0]dec‐5‐ene (TBD) was used for the rapid synthesis of 3‐hydroxyisoindolin‐1‐ones from 3‐alkylidenephthalides. The transformation occurs at room temperature and requires less solvent than traditional methods, providing a more sustainable synthetic option to access 3‐hydroxyisoindolin‐1‐ones with broad scope. Elaboration of the products to diverse scaffolds as well as synthesis of biologically active compounds are demonstrated.