TY - JOUR

T1 - Ferromagnetically Coupled S=1 Chains in Crystals of Verdazyl-Nitronyl Nitroxide Diradicals

AU - Tretyakov, Evgeny V.

AU - Zhivetyeva, Svetlana I.

AU - Petunin, Pavel V.

AU - Gorbunov, Dmitry E.

AU - Gritsan, Nina P.

AU - Bagryanskaya, Irina Yu

AU - Bogomyakov, Artem S.

AU - Postnikov, Pavel S.

AU - Kazantsev, Maxim S.

AU - Trusova, Marina E.

AU - Shundrina, Inna K.

AU - Zaytseva, Elena V.

AU - Parkhomenko, Dmitriy A.

AU - Bagryanskaya, Elena G.

AU - Ovcharenko, Victor I.

N1 - Funding Information: This research was supported by the Ministry of Science and Higher Education of the Russian Federation (State Project “Science” No. FSWW‐2020‐0011) and the Russian Science Foundation (grant No. 18‐13‐00173, synthesis and characterization). A.S.B. and V.I.O. are thankful to the Russian Science Foundation (grant No. 18‐13‐00380, magnetochemistry). D.E.G. and N.P.G. acknowledge support of the Ministry of Science and Higher Education of the Russian Federation (project No. 0304‐2017‐0008) and the Irkutsk Supercomputer Centre of the Siberian Branch of the Russian Academy of Sciences for computational resources. The authors would like to acknowledge the Multi‐Access Chemical Research Center SB RAS for spectral and analytical measurements. Publisher Copyright: © 2020 Wiley-VCH GmbH Copyright: Copyright 2020 Elsevier B.V., All rights reserved.

PY - 2020/11/9

Y1 - 2020/11/9

N2 - Thermally stable organic diradicals with a triplet ground state along with large singlet-triplet energy gap have significant potential for advanced technological applications. A series of phenylene-bridged diradicals with oxoverdazyl and nitronyl nitroxide units were synthesized via a palladium-catalyzed cross-coupling reaction of iodoverdazyls with a nitronyl nitroxide-2-ide gold(I) complex with high yields. The diradicals exhibit high stability and do not decompose in an inert atmosphere up to 180 °C. For the diradicals, both substantial AF (ΔEST≈−64 cm−1) and FM (ΔEST≥25 and 100 cm−1) intramolecular exchange interactions were observed. The sign of the exchange interaction is determined both by the bridging moiety (para- or meta-phenylene) and by the type of oxoverdazyl block (C-linked or N-linked). Upon crystallization, diradicals with the triplet ground state form unique one-dimensional exchange-coupled chains with strong intra- and weak inter-diradical ferromagnetic coupling.

AB - Thermally stable organic diradicals with a triplet ground state along with large singlet-triplet energy gap have significant potential for advanced technological applications. A series of phenylene-bridged diradicals with oxoverdazyl and nitronyl nitroxide units were synthesized via a palladium-catalyzed cross-coupling reaction of iodoverdazyls with a nitronyl nitroxide-2-ide gold(I) complex with high yields. The diradicals exhibit high stability and do not decompose in an inert atmosphere up to 180 °C. For the diradicals, both substantial AF (ΔEST≈−64 cm−1) and FM (ΔEST≥25 and 100 cm−1) intramolecular exchange interactions were observed. The sign of the exchange interaction is determined both by the bridging moiety (para- or meta-phenylene) and by the type of oxoverdazyl block (C-linked or N-linked). Upon crystallization, diradicals with the triplet ground state form unique one-dimensional exchange-coupled chains with strong intra- and weak inter-diradical ferromagnetic coupling.

KW - BS-DFT and high level calculations

KW - ferromagnetic chain

KW - high-spin molecules

KW - nitroxides

KW - triplet diradicals

KW - DESIGN

KW - RADICALS

UR - http://www.scopus.com/inward/record.url?scp=85092590958&partnerID=8YFLogxK

U2 - 10.1002/anie.202010041

DO - 10.1002/anie.202010041

M3 - Article

C2 - 32715591

AN - SCOPUS:85092590958

VL - 59

SP - 20704

EP - 20710

JO - Angewandte Chemie - International Edition

JF - Angewandte Chemie - International Edition

SN - 1433-7851

IS - 46

ER -