Pro-aromaticity Enabled Dealkenylative Functionalizations via Photo-Excitation and Oxidation

Chemistry. 2023 May 11;29(27):e202203425. doi: 10.1002/chem.202203425. Epub 2023 Mar 28.

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.

Keywords: C−C cleavage; dealkenylation; oxidation; photochemistry; radical reaction.