A Facile Route to Pyrazolo[1,2‐a]cinnoline via Rhodium(III)‐catalyzed Annulation of Pyrazolidinoes and Iodonium Ylides

Abstract A rhodium(III)‐catalysed cascade C−H bond activation/intramolecular cyclization of pyrazolidiones with iodonium ylide has been described, leading to the formation of various pyrazolo[1,2‐a]cinnolines. Herein, iodonium ylide serves as a carbene precursor. This protocol exhibits good regioselectivity and high functional group tolerability under mild reaction conditions.