Photochemical C-P Bond Formation via Direct EDA Complexation between P-Reagents and Haloheteroarenes without Catalysts and Bases.

The carbon-phosphorus (C-P) bond is a key motif in pharmaceuticals, agrochemicals, and materials. Photochemical methods have recently emerged as mild, sustainable routes for C-P construction. In this regard, the electron donor-acceptor (EDA) strategy has been applied in photochemical C-P construction, which typically requires an external base as a donor to engage electron-deficient heteroarenes. Taking advantage of the inherent electron-donating ability of trivalent phosphorus species, we demonstrate that P-reagents directly serve as the electron donor, forming a photoactive EDA complex with the electron-deficient quinoxalines, thus enabling a catalyst- and base-free platform to afford diverse C-P products in good yields. This operationally simple protocol demonstrates excellent functional group tolerance and offers a streamlined approach to functionalized heteroaryl phosphorus derivatives with broad synthetic utility.