Synthesis of 3-Aminopiperidines via I(III)-Mediated Olefin Diamination with (Hetero)aryl Nucleophiles

3-Aminopiperidines are a valuable motif present in small molecule pharmaceuticals and bioactive natural products. Synthesis of these moieties via olefin diamination would be an attractive approach, however significant challenges remain with regards to both regioselectivity and exogenous nucleophile scope. Herein, we report a metal-free olefin diamination via a heterocyclic group transfer (HGT) reaction of I(III) N-HVI reagents, giving rise to 3-aminopiperidines with high selectivity. The HGT strategy leverages heteroarenes as oxidatively masked amine nucleophiles, giving rise to (hetero)arylonium salt products which are isolated via simple trituration and provide a versatile handle for downstream diversification. This represents only the second 6-endo selective I(III)-mediated diamination reaction and mechanistic studies indicate ring opening of an intermediate aziridinium ion is responsible for the 6-endo selectivity.

Automated summary

A metal-free olefin diamination via a heterocyclic group transfer (HGT) reaction of I(III) N-HVI reagents has been reported, resulting in the synthesis of 3-aminopiperidines with high selectivity. The HGT strategy utilizes heteroarenes as oxidatively masked amine nucleophiles to produce (hetero)arylonium salt products, which can be easily isolated and further diversified. Mechanistic studies suggest that the 6-endo selectivity is attributed to the ring opening of an intermediate aziridinium ion.