C–H activation reactions enable chemists to unveil new retrosynthetic disconnections and streamline conventional synthetic approaches. A long-standing challenge in C–H activation is the inability to distinguish electronically and sterically similar C–H bonds. Although numerous synergistic combinations of transition-metal complexes and chelating directing groups have been utilized to distinguish C–H bonds, undirected regioselective C–H functionalization strategies remain elusive. Here we report a regioselective C–H activation/amination reaction of various unsymmetrical dialkyl-substituted alkenes. The regioselectivity of C–H activation is correlated to the electronic properties of allylic C–H bonds indicated by the corresponding 1JCH coupling constants. A linear relationship between the difference in the 1JCH coupling constants of the two competing allylic C–H bonds (Δ1JCH) and the C–H activation barriers (ΔΔG‡) has also been determined.
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We thank NIGMS (GM80442) for support. We thank J. Decatur for assistance with determining 1JCH coupling constants.
The authors declare no competing interests.
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Lei, H., Rovis, T. A site-selective amination catalyst discriminates between nearly identical C–H bonds of unsymmetrical disubstituted alkenes. Nat. Chem. 12, 725–731 (2020). https://doi.org/10.1038/s41557-020-0470-z