Rh(III)-catalyzed [3 + 3] spirocyclization of 3-aryl-3-hydroxyisoindolinones with vinylene carbonate as a three-atom unit.

Abstract

A [3 + 3] annulation of 3-aryl-3-hydroxyisoindolinones for the efficient synthesis of isoindolinone-derived spiroisochromenes is reported. In this Rh(III)-catalyzed spirocyclization reaction, vinylene carbonate is used as the coupling partner and acts as a three-atom synthon (C-C-O) through the decarboxylation process. This atom-economic reaction worked efficiently under mild conditions via a C-H activation pathway. It is the first example where 3-aryl-3-hydroxyisoindolinones are used as the building blocks to construct spiroheterocycles.