Long‐Wavelength Light‐Induced Group 13–15 Elementalization Reactions of Alkenes/Alkynes

We present di-tert-butyl peroxide (DTBP)-catalyzed long-wavelength light-induced Group 13, 14, and 15 elementalizations of alkenes and alkynes, through in situ production of tert-butyl radicals, followed by a hydrogen-atom-transfer process generating silyl, germyl, stannyl, alkyl, boryl, and phosphoryl radicals. This mild and photosensitizer-free methodology employing blue (450 nm)/green (530 nm)/orange (600 nm) LEDs affords high chemoselectivity and broad functional group tolerance compared to conventional use of shorter-wavelength light. Synthetic, spectroscopic, and computational data are consistent with a vibration-mediated photolysis mechanism of DTBP involving electronic excitation from vibrationally excited ground states (S₀μ_n) to the excited state (S₀μ_n→S_n transitions), driven by ultraweak absorption of long-wavelength visible light.