Mechanistic Studies of Cobalt-Catalyzed C(sp²)-H Borylation of Five-Membered Heteroarenes with Pinacolborane.

ABSTRACT: Studies into the mechanism of cobalt-catalyzed C(sp²)-H borylation of five-membered heteroarenes with pinacolborane (HBPin) as the boron source established the catalyst resting state as the trans-cobalt(III) dihydride boryl, (^iPrPNP)Co(H)₂(BPin) (^iPrPNP = 2,6-(ⁱPr₂PCH₂)₂(C₅H₃N)), at both low and high substrate conversions. The overall first-order rate law and observation of a normal deuterium kinetic isotope effect on the borylation of benzofuran versus benzofuran-2-d₁ support H₂ reductive elimination from the cobalt(III) dihydride boryl as the turnover-limiting step. These findings stand in contrast to that established previously for the

SUBMITTER: Obligacion JV 

PROVIDER: S-EPMC5822728 | biostudies-literature | 2017 Jul

REPOSITORIES: biostudies-literature