An environmentally friendly synthesis of polysubstituted pyrroles in ionic liquid was achieved via a gold-catalyzed propargylic substitution/hydration/amination/cycloisomerization sequence. Treatment of propargylic alcohols, 1,3-dicarbonyl compounds, and arylamines in the presence of AuBr3 (5 mol%) and AgOTf (15 mol%) in EMIMNTf2 afforded polysubstituted pyrroles in good to high yield. This reaction involves reacting arylamine with the hydrated propargylic substitution product formed as an intermediate to yield polysubstituted pyrroles.
Chiaki et al. (Sun,) studied this question.