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Directed Hydroxylation of sp2 and sp3 C-H Bonds Using Stoichiometric Amounts of Cu and H2O2.

ABSTRACT: The use of copper for C-H bond functionalization, compared to other metals, is relatively unexplored. Herein, we report a synthetic protocol for the regioselective hydroxylation of sp2 and sp3 C-H bonds using a directing group, stoichiometric amounts of Cu and H2O2. A wide array of aromatic ketones and aldehydes are oxidized in the carbonyl ?-position with remarkable yields. We also expanded this methodology to hydroxylate the ?-position of alkylic ketones. Spectroscopic characterization, kinetics, and density functional theory calculations point toward the involvement of a mononuclear LCuII(OOH) species, which oxidizes the aromatic sp2 C-H bonds via a concerted heterolytic O-O bond cleavage with concomitant electrophilic attack on the arene system.

SUBMITTER: Trammell R

PROVIDER: S-EPMC6603193 | biostudies-literature | 2019 Jun

REPOSITORIES: biostudies-literature

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Directed Hydroxylation of sp2 and sp3 C-H Bonds Using Stoichiometric Amounts of Cu and H2O2.

Trammell Rachel R D'Amore Lorenzo L Cordova Alexandra A Polunin Pavel P Xie Nan N Siegler Maxime A MA Belanzoni Paola P Swart Marcel M Garcia-Bosch Isaac I

Inorganic chemistry 20190514 11

The use of copper for C-H bond functionalization, compared to other metals, is relatively unexplored. Herein, we report a synthetic protocol for the regioselective hydroxylation of sp2 and sp3 C-H bonds using a directing group, stoichiometric amounts of Cu and H2O2. A wide array of aromatic ketones and aldehydes are oxidized in the carbonyl γ-position with remarkable yields. We also expanded this methodology to hydroxylate the β-position of alkylic ket ...[more]

PMID: 31084018

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