School of Pharmacy, Sungkyunkwan University, Suwon 16419, Republic of Korea.
J Org Chem. 2021 Sep 3;86(17):12247-12256. doi: 10.1021/acs.joc.1c01558. Epub 2021 Aug 18.
The direct functionalization of -heterocycles is a vital transformation for the development of pharmaceuticals, functional materials, and other chemical entities. Herein, the transition-metal-free alkylation and acylation of C(sp)-H bonds in biologically relevant 2-benzoxazinones with 1,4-dihydropyridines as readily accessible radical surrogates is described. Excellent functional group compatibility and a broad substrate scope were attained. Gram-scale reaction and transformations of the synthesized adducts via Suzuki coupling with heteroaryl boronic acids demonstrated the synthetic potential of the developed protocol.