Mimics of Pincer Ligands: An Accessible Phosphine-Free N-(Pyrimidin-2-yl)-1,2-azole-3-carboxamide Framework for Binuclear Pd(II) Complexes and High-Turnover Catalysis in Water

Alexey V Kletskov; Nikolay A Bumagin; Sergey K Petkevich; Evgenij A Dikusar; Alexander S Lyakhov; Ludmila S Ivashkevich; Iryna A Kolesnik; Vladimir I Potkin

doi:10.1021/acs.inorgchem.0c01035

Mimics of Pincer Ligands: An Accessible Phosphine-Free N-(Pyrimidin-2-yl)-1,2-azole-3-carboxamide Framework for Binuclear Pd(II) Complexes and High-Turnover Catalysis in Water

Inorg Chem. 2020 Aug 3;59(15):10384-10388. doi: 10.1021/acs.inorgchem.0c01035. Epub 2020 Jul 20.

Authors

Alexey V Kletskov^{1

2

3}, Nikolay A Bumagin¹, Sergey K Petkevich², Evgenij A Dikusar², Alexander S Lyakhov⁴, Ludmila S Ivashkevich⁴, Iryna A Kolesnik², Vladimir I Potkin²

Affiliations

¹ Chemical Department, M.V. Lomonosov Moscow State University, Leninskie Gory, 1/3, Moscow 119991, Russian Federation.
² Institute of Physical Organic Chemistry, National Academy of Sciences of Belarus, Surganova Str., 13, Minsk 220072, Belarus.
³ Peoples' Friendship University of Russia (RUDN University), Miklukho-Maklaya Str., 6, Moscow 117198, Russian Federation.
⁴ Research Institute for Physical Chemical Problems of Belarusian State University, Leningradskaya Str., 14, Minsk 220006, Belarus.

PMID: 32687332
DOI: 10.1021/acs.inorgchem.0c01035

Abstract

We report for the first time cyclic phosphine-free "head to tail" N,N,N pincer-like (pincer complexes mimicking) N-(pyrimidin-2-yl)-1,2-azole-3-carboxamide Pd(II) complexes with deprotonated amide groups as high-turnover catalysts (TON up to 10⁶, TOF up to 1.2 × 10⁷ h^-1) for cross-coupling reactions on the background of up to quantitative yields under Green Chemistry conditions. The potency of the described catalyst family representatives was demonstrated in Suzuki-Miyaura, Mizoroki-Heck, and Sonogashira reactions on industrially practical examples. Corresponding ligands could be synthesized based on readily available reagents through simple chemical transformations. Within the complex structures, a highly unusual 1,3,5,7-tetraza-2,6-dipalladocane frame could be observed.