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High‐spin organic tetraradicals with significant intramolecular exchange interactions have high potential for advanced technological applications and fundamental research, but those synthesized to date possess limited stability and processability. In this work, we have designed a tetraradical based on the Blatter's radical and nitronyl nitroxide radical moieties and successfully synthesized it by using the palladium‐catalyzed cross‐coupling reaction of a triiodo‐derivative of the 1,2,4‐benzotriazinyl radical with gold(I) nitronyl nitroxide‐2‐ide complex in the presence of a newly developed efficient catalytic system. The molecular and crystal structure of the tetraradical was confirmed by X‐ray diffraction analysis. The tetraradical possesses good thermal stability with decomposition onset at ∼150 °C under an inert atmosphere and exhibits reversible redox waves at −0.54 and 0.45 V versus Ag/AgCl. The magnetic properties of the tetraradical were characterized by SQUID magnetometry of polycrystalline powders and EPR spectroscopy in various matrices. The collected data, analyzed by using high‐level quantum chemical calculations, confirmed that the tetraradical has a triplet ground state and a nearby excited quintet state. The unique high stability of the prepared triazinyl‐nitronylnitroxide tetraradical is a new milestone in the field of creating high‐spin systems. [ABSTRACT FROM AUTHOR]

A simple and highly effective methodology for the cross-coupling of heteroaryl iodides with NN–AuPPh3 at room temperature is reported. The protocol is based on a novel catalytic system consisting of Pd2(dba)3·CHCl3 and the phosphine ligand MeCgPPh having an adamantane-like framework. The present protocol was found to be well compatible with various heteroaryl iodides, thus opening new horizons in directed synthesis of functionalized nitronyl nitroxides and high-spin molecules. [ABSTRACT FROM AUTHOR]

Nitronyl nitroxides are functional building blocks in cutting‐edge research fields, such as the design of molecular magnets, the development of redox and photoswitchable molecular systems and the creation of redox‐active components for organic and hybrid batteries. The key importance of the nitronyl nitroxide function is to translate molecular‐level‐optimized structures into nano‐scale devices and new technologies. In spite of great importance, efficient and versatile synthetic approaches to these compounds still represent a challenge. Particularly, methods for the direct introduction of a nitronyl nitroxide moiety into aromatic systems possess many limitations. Here, we report gold derivatives of nitronyl nitroxide that can enter Pd(0)‐catalysed cross‐coupling reactions with various aryl bromides, affording the corresponding functionalized nitronyl nitroxides. Based on the high thermal stability and enhanced reactivity in catalytic transformation, a new reagent is suggested for the synthesis of radical systems via a universal cross‐coupling approach. [ABSTRACT FROM AUTHOR]