Le-Hua Ye, Xiao Cheng, Zi-Qi Zhu* and Feng Shi*, Synthesis of Indole-Fused Chromane-Based Spirooxindoles via Brønsted Acid-Catalyzed Regioselective [5+1] Annulation, Eur. J. Org. Chem. 2025, e202401405. DOI:10.1002/ejoc.202401405