Pro-aromaticity Enabled Dealkenylative Functionalizations via Photo-Excitation and Oxidation
Si-Cong Chen1, Qi Zhu1, Han Chen1
1Key Laboratory of Bioorganic Chemistry and Molecular Engineering, Ministry of Education and Beijing National Laboratory for Molecular Science, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, P. R. China.
Abstract:
A general and practical approach for diverse dealkenylative functionalization of olefin-containing substrates has been developed through the one-pot formation and utilization of pro-aromatic 1,4-dihydropyridazines using tetrazine as the key cycloaddition reagent. Triggered by either excitation or oxidation, the targeted C-C bonds in the 1,4-dihydropyridazine intermediates could be readily cleaved to generate alkyl radicals for subsequent transformations. Diverse carbon-carbon and carbon-hetero bond forming protocols, including Giese-type addition, hydrazination, borylation, Minisci-type alkylation, copper-catalyzed NH alkylation, acylation, alkynylation, cyanation, and azidation, are achieved in a highly modular fashion.
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