Synthesis of fluorescent heterocycles via a Knoevenagel/[4 + 1]-cycloaddition cascade using acetyl cyanide. Issue 29 (7th July 2017) - Martinez-Ariza, Guillermo
Abstract : Acetyl cyanide is utilized to synthesize fluorescent indolizines, benzo[ d ]pyrrolo[2, 1- b ]thiazoles, and pyrrolo[1, 2- a ]pyrazines in a single step. Abstract : A concise one-pot three-component reaction that affords fluorescent indolizines, benzo[ d ]pyrrolo[2, 1- b ]thiazoles, and pyrrolo[1, 2- a ]pyrazines is reported. The methodology involves the formation of a heterocyclic 1-aza-1, 3-diene derived from a Knoevenagel condensation between an aldehyde and 2-methyl-ene-cyano aza-heterocycles, followed by [4 + 1] cycloaddition of acetyl cyanide behaving as a non-classical isocyanide replacement.