New approaches to ondansetron and alosetron inspire a versatile, flow photochemical method for indole synthesis

An oxidative photocyclisation of N-arylenaminones to indoles is described, that mirrors the Fischer indole synthesis but uses anilines in place of arylhydrazines. Its value is exemplified with new approaches to the WHO-listed APIs ondansetron and alosetron.

Automated summary

An oxidative photocyclisation of N-arylenaminones to indoles is presented, using anilines instead of arylhydrazines in a process reminiscent of the Fischer indole synthesis. This method demonstrates new approaches to synthesizing WHO-listed APIs such as ondansetron and alosetron.