Visible-light-induced three-component alkylpyridylation of alkenes
enabled by electron donor-acceptor complex
Abstract
Visible-light-induced difunctionalization of alkenes is a powerful
strategy for constructing complex molecules. Herein, we disclose a
three-component 1,2-alkylpyridylation of alkenes under mild and
photosensitizers-free conditions. UV-vis absorption spectroscopy studies
and NMR titration experiments indicate that the formation of an EDA
complex between 4-alkyl-DHPs and 4-cyanopyridines. Primary, secondary,
and tertiary C(sp3)-centered radicals were formed by homolytic cleavage
of 4-alkyl-DHPs. Gram-scale synthesis and late-stage functionalization
of medicinally relevant molecules showed the synthetic potential of our
methodology.