Tungsten catalysed decarboxylative [3 + 2] cycloaddition aromatization: one-pot synthesis of trifluoromethyl-pyrrolo[2,1-a]isoquinolines with visible light irradiation

Abstract

The pyrrolo[2,1-a]isoquinoline core structure is prevalent in marine natural products and its fluorinated derivatives are potential medicinal compounds. Herein is described a tungsten-catalysed decarboxylative [3 + 2] cycloaddition aromatization process that could be used to construct trifluoromethyl-pyrrolo[2,1-a]isoquinolines. This photocatalytic reaction tolerates a panel of functional groups including ester, nitrile, ketone and alkene (24 examples, up to 94% yield). The pharmaceutically useful trifluoromethyl substituted lamellarin derivatives and late-stage derivatization of drugs are facilely accessible via the current synthetic approach.