Twofold Radical-Based Synthesis of N,C-Difunctionalized Bicyclo[1.1.1]pentanes

Bicyclo[1.1.1]pentylamines (BCPAs) are of growing importance to the pharmaceutical industry as sp(3)-rich bioisosteres of anilines and N-tert-butyl groups. Here we report a facile synthesis of 1,3-disubstituted BCPAs using a twofold radical functionalization strategy. Sulfonamidyl radicals, generated through fragmentation of alpha-iodoaziridines, undergo initial addition to [1.1.1]propellane to afford iodo-BCPAs; the newly formed C-I bond in these products is then functionalized via a silyl-mediated Giese reaction. This chemistry also translates smoothly to 1,3-disubstituted iodo-BCPs. A wide variety of radical acceptors and iodoBCPAs are accommodated, providing straightforward access to an array of valuable aniline-like isosteres.

Automated summary

A facile synthesis of 1,3-disubstituted BCPAs using a twofold radical functionalization strategy is reported, allowing for straightforward access to an array of valuable aniline-like isosteres.