TY - JOUR

T1 - Palladium-Aminopyridine Catalyzed C−H Oxygenation: Probing the Nature of Metal Based Oxidant

AU - Lubov, Dmitry P.

AU - Bryliakova, Anna A.

AU - Samsonenko, Denis G.

AU - Sheven, Dmitriy G.

AU - Talsi, Evgenii P.

AU - Bryliakov, Konstantin P.

N1 - Funding Information: DPL, EPT, KPB thank Russian Science Foundation (project 17‐13‐01117) for financial support of this work. AAB acknowledges the access to the supercomputer facilities of the Computing Centre of Novosibirsk State University. The authors thank Dr. M.V. Shashkov (Center of Collective Use “National Center of Catalysis Research”) for the GC‐MS measurements and the Multi‐Access Chemical Research Center SB RAS for spectral and analytical measurements. D. G. Samsonenko and D. G. Sheven acknowledge budget funding by the Ministry of Science and Higher Education of the Russian Federation for the Nikolaev Institute of Inorganic Chemistry SB RAS, projects 121031700321‐3 and 121031700313‐8, respectively. Publisher Copyright: © 2021 Wiley-VCH GmbH

PY - 2021/12/15

Y1 - 2021/12/15

N2 - A mechanistic study of direct selective oxidation of benzylic C(sp3)−H groups with peracetic acid, catalyzed by palladium complexes with tripodal amino-tris(pyriylmethyl) ligands, is presented. The oxidation of arylalkanes having secondary and tertiary benzylic C−H groups, predominantly yields, depending on the substrate and conditions, either the corresponding ketones or alcohols. One of the three 2-pyriylmethyl moieties, which is pending in the starting catalyst, apparently, facilitates the active species formation and takes part in stabilization of the high-valent Pd center in the active species, occupying the axial coordination site of palladium. The catalytic, as well as isotopic labeling experiments, in combination with ESI-MS data and DFT calculations, point out palladium oxyl species as possible catalytically active sites, operating essentially via C−H abstraction/oxygen rebound pathway. For the ketones formation, O−H abstraction/в-scission mechanism has been proposed.

AB - A mechanistic study of direct selective oxidation of benzylic C(sp3)−H groups with peracetic acid, catalyzed by palladium complexes with tripodal amino-tris(pyriylmethyl) ligands, is presented. The oxidation of arylalkanes having secondary and tertiary benzylic C−H groups, predominantly yields, depending on the substrate and conditions, either the corresponding ketones or alcohols. One of the three 2-pyriylmethyl moieties, which is pending in the starting catalyst, apparently, facilitates the active species formation and takes part in stabilization of the high-valent Pd center in the active species, occupying the axial coordination site of palladium. The catalytic, as well as isotopic labeling experiments, in combination with ESI-MS data and DFT calculations, point out palladium oxyl species as possible catalytically active sites, operating essentially via C−H abstraction/oxygen rebound pathway. For the ketones formation, O−H abstraction/в-scission mechanism has been proposed.

KW - C−H activation

KW - intermediate

KW - mechanism

KW - oxyl

KW - palladium

KW - peracetic acid

KW - selective oxidation

UR - http://www.scopus.com/inward/record.url?scp=85118583343&partnerID=8YFLogxK

U2 - 10.1002/cctc.202101345

DO - 10.1002/cctc.202101345

M3 - Article

AN - SCOPUS:85118583343

VL - 13

SP - 5109

EP - 5120

JO - ChemCatChem

JF - ChemCatChem

SN - 1867-3880

IS - 24

ER -