Reductive CO2 Fixation via Tandem C-C and C-N Bond Formation: Synthesis of Spiro-indolepyrrolidines.

We describe herein a tandem C-C and C-N bond-forming reaction in the reductive functionalization of CO2, an abundant and cheap C1 chemical feedstock. This catalytic metal-free CO2 fixation afforded spiro-indolepyrrolidines by dearomatization of tryptamine derivatives with broad scope and good functional group tolerance under mild conditions.