Metal-free direct carbofunctionalization of [1.1.1]propellane and [3.1.1]propellane driven by light.

1,3-disubstituted bicyclo[1.1.1]pentanes (BCPs), as bioisosteres of para-disubstituted benzenes still play a pivotal role in pharmaceutical industry and organic materials. In previous reports, their synthesis normally requires muti-step or multi-component reactions and involves the participation of transition metals, photocatalysts and radical initiators. Here, we report a modular synthesis of 1,3-disubstituted BCPs from [1.1.1]propellane, by forming two C-C bonds without involvement of transition metals and photocatalysts. Moreover, this strategy could be extended to [3.1.1]propellane for the preparation of 1,5-disubstituted bicyclo[3.1.1]heptanes (BCHs). This tactic also allows introduction silyl groups into the BCP cores by forming a C-Si bond, providing access to a rare silyl substituted BCP framework.