Perimidine directed Rh(iii)-catalyzed [4 + 1] and [4 + 2] annulations: synthesis of perimidine linked spiro-succinimides and isoquinolines

Abstract

We report a novel Rh(III)-catalyzed perimidine-directed C–H activation strategy for the synthesis of perimidine-fused heterocycles using various types of alkenes. The reaction of 2-aryl perimidines with maleimides in the presence of the [RhCp*Cl₂]₂ catalyst facilitates a cascade [4 + 1] spiro-annulation, affording perimidine-linked isoindoles spiro-fused with succinimides. Conversely, vinylene carbonates provided a fused six-membered ring via a [4 + 2] cyclization, yielding perimidine-fused isoquinolines. This methodology is useful for synthesizing a library of polycyclic perimidine-fused heterocycles.