Brønsted-acid-catalyzed selective Friedel–Crafts monoalkylation of isatins with indolizines in water. Issue 37 (18th September 2020) - Guidotti, Bruno Boni
Abstract : Controlled Friedel–Crafts monoalkylations of indolizines with isatins have been achieved by using water as the solvent. This is the first organocatalyzed indolizine 1, 2-addition reported. Abstract : The controlled mono-addition of indolizines to isatins under very mild conditions is described. The reaction occurs in water using diphenylphosphate as the catalyst, which is dramatically accelerated by surfactant addition. 3-Hydroxy-3-indolizinyl-2-oxindole scaffolds were synthesized in up to >99% yield. Notably, in organic solvents only bis-addition products were observed.