Long-Wavelength Light-Induced Group 13-15 Elementalization Reactions of Alkenes/Alkynes
Haruka Iimuro1, Antônio Junio Araujo Dias1, Ken Tanaka1
1Department of Chemical Science and Engineering, Institute of Science Tokyo, O-okayama, Meguro-ku, Tokyo, 152-8550, Japan.
Abstract:
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 (S0μn) to the excited state (S0μn→Sn transitions), driven by ultraweak absorption of long-wavelength visible light.
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