Chromoselective Control for Aminoalkylation of CF3‑Alkenes through Low-Energy Photoredox Catalysis
Year: 2026
Type: preprint
Abstract: Recent advances in chromoselective photoredox catalysis have demonstrated that light wavelength can serve as a powerful and orthogonal reaction parameter, enabling divergent reactivity from a single catalytic system. Building on recent advances in the sequential decarboxylative/defluorinative aminoalkylation of trifluoromethyl-substituted alkenes, we report a divergent, wavelength-dependent strategy for the site-selective functionalization of N-arylglycines. High-throughput experimentation (HTE) was used to systematically screen photocatalysts and irradiation wavelengths to identify the most suitable divergent conditions. Interestingly, using [Ru(bpy)3]2+ as photocatalyst, irradiation with blue light promotes efficient difunctionalization of CF3-alkenes with N-arylglycines, affording monofluoroalkenyl-1,5-diamines, while switching the irradiation to red light enables selective monofunctionalization, delivering the corresponding gem-difluoroalkenyl amine intermediates exclusively under otherwise identical conditions, via a spin-forbidden transition pathway. This wavelength-governed switchable reactivity provides a powerful and tunable platform for the controlled radical modification of amino acids, expanding the synthetic utility of visible-light photoredox catalysis in divergent amine synthesis. Mechanistic investigations using photoelectrochemistry and TD-DFT have revealed notably a photo-excitation of intermediates, allowing for the second functionalization to whether happens or not, based on the irradiation wavelength used.
Source: ChemRxiv
Language: English
Subfield: Organic Chemistry
Field: Chemistry
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W7221532684