Catalyst-Free [3+2] Cycloaddition of Isoquinolinium/Pyridinium Ylides and Electron-Deficient Alkenes

The development of simple-to-operate methods for the preparation of indolizidine derivatives are of great importance. A mild one-pot protocol for the [3+2] cycloaddition of isoquinolinium/pyridinium ylides and electron-deficient alkenes using NaBH3CN as reductant has been developed. The protocol has a broad substrate scope (more than 40 examples) and provides various novel hexahydroindolizidine derivatives in high yields and excellent diastereoselectivities (up to >20/1).

Automated summary

The development of a simple and efficient method for preparing indolizidine derivatives is of great importance. A one-pot protocol using NaBH3CN as reductant has been developed for the [3+2] cycloaddition of isoquinolinium/pyridinium ylides and electron-deficient alkenes, providing a wide range of novel hexahydroindolizidine derivatives in high yields and excellent diastereoselectivities.