Bridged-Type Selective Intramolecular Nitrone–Alkene Cycloaddition: Computational Chemistry-Inspired Regioselectivity Control

A regioselective intramolecular nitrone-alkene cycloaddition for synthesizing oxazabicyclo ring-fused indoles is reported. Computational studies guided the development of optimal conditions using In(OTf)₃ as a Lewis acidic reagent. This method demonstrates a broad substrate scope, forming seven- and eight-membered carbocycles with various substituents, and provides a versatile route to complex nitrogen-containing scaffolds with potential applications in medicinal chemistry and the total synthesis of biologically active compounds.