Computational Study of the Ni-Catalyzed C-H Oxidative Cycloaddition of Aromatic Amides with Alkynes.

ABSTRACT: The mechanism of Ni-catalyzed ortho C(sp²)-H oxidative cycloaddition of aromatic amides with internal alkynes containing 2-pyridinylmethylamine directing group was investigated using density functional theory (DFT) calculations. The C-H cleavage step proceeds via σ-complex-assisted metathesis (σ-CAM) with an alkenyl-Ni(II) complex. This is in contrast to the more common carboxylate/carbonate-assisted concerted metalation-deprotonation mechanism in related Ni-catalyzed C-H bond functionalization reactions with N,N-bidentate directing groups. In this reaction, the alkyne not only serves as the coupling partner, but also facilitates the σ-CAM C-H metalation both kinetically and thermodynamically. The subsequent functionalization of the five-membered nickelacycl

SUBMITTER: Omer HM 

PROVIDER: S-EPMC6648058 | biostudies-literature | 2019 Mar

REPOSITORIES: biostudies-literature