Semi-heterogeneous Dual Iron/Photocatalytic Decarboxylative C(sp3)-C(sp3) Cross-Coupling via Radical Sorting

Abstract

The selective radical C(sp3)-C(sp3) cross-coupling reaction between two distinct radicals remains a long-standing challenge due to its inherently statistical nature, which results in complex product distribution. This can be resolved by either the persistent radical effect (PRE) or radical sorting strategy through SH2 mechanism. Herein, we demonstrated a highly efficient decarboxylative C(sp3)-C(sp3) cross-coupling reaction employing mesoporous graphitic carbon nitride (mpg-CN) as a recyclable semi-heterogeneous photocatalyst in combination with an iron porphyrin cocatalyst under mild reaction conditions. Notably, this system tolerates diverse C(sp3) progenitors including carboxylic acid, redox active esters, potassium trifluoroborates, Katritzky salts, and dihydropyridines, therefore, enabling the synthesis of diverse 3°-1°, 2°-1° and 1°-1° cross-coupling products in generally good yields. Furthermore, the successful gram-scale synthesis and recyclability of the mpg-CN photocatalyst highlights its potential for industrial applications.