Molecular Magnets: The Synthesis and Characterization of High‐Spin Nitrenes

Abstract

Among all C-, N-, and O-centered polyradicals, high-spin nitrenes possess the largestm agnetic anisotropy and are of considerable interest as multi-level molecular spin systems for explorationo fo rganic molecular magnetism and quantum information processing. Although the first representatives of quintet and septet nitrenes were obtained almost 50 years ago, the experimental and theoretical studies of these highly reactive speciesb ecamep ossible only recently ,o wing to new achievements in molecular spectroscopy and computationalc hemistry.M eanwhile, dozens of various quintet dinitrenes and septettrinitrenes were successfully characterized by IR, UV/Vis,a nd EPR spectroscopy,t hus providing important information about the electronic structure, magnetic properties and reactivity of these compounds.

Pyrene-Enhanced Ferromagnetic Interaction in a FeCl4–-Based Poly(ionic liquid)s Organic Magnet

“…After rotary evaporation and vacuum drying, the pure Compound A was obtained as white needle crystals, yield 86%. 1 H NMR (400 MHz, CDCl 3 ): δ 6.11 (t, J = 1.7 Hz, 2H), 3.37 (dd, J = 14.2, 7.0 Hz, 6H), 3.25 (dd, J = 2.8, 1.5 Hz, 2H), 1.84−1.71 (m, 3H), 1.68−1.47 (m, 3H). (2.5203 g, 30.0 mmol) were added to a Schlenk bottle equipped with a condenser and dissolved in a mixed solvent with 100 mL of tetrahydrofuran (THF) and 20 mL of distilled water.…”

“…The pure Compound D was obtained as a pale-yellow solid, yield 83%. 1 H NMR (400 MHz, DMSO-d 6 ): δ 8.33 (d, J = 7.9 Hz, 2H), 8.18 (q, J = 9.4 Hz, 4H), 8.02 (d, J = 7.8 Hz, 2H), 7.58 (dd, J = 8.5, 3.4 Hz, 4H), 7.19 (t, J = 8.8 Hz, 4H), 6.10 (s, 2H), 4.17 (t, J = 6.2 Hz, 2H), 4.10 (t, J = 6.1 Hz, 2H), 3.69 (t, J = 6.6 Hz, 2H), 3.40−3.30 (m, 4H), 3.29 (s, 2H), 2.14−2.01 (m, 2H), 2.00−1.89 (m, 2H), 1.80−1.63 (m, 2H), 1.65−1.53 (m, 4H). 13 The reaction was maintained at 80 °C for 48 h. After that, the mixture was concentrated and precipitated with excess anhydrous diethyl ether to obtain a white solid.…”

“…Organic magnets , (also called molecular magnets) including single molecular magnet, − single chain magnet, polyradicals, and so on are molecular-based magnets which possess unpaired electrons in either p- or d-/f-orbitals that contribute to the magnetic ordering and/or magnetic spin coupling. , From the beginning of their discovery, organic magnets are expected to exhibit novel properties compared to the traditional inorganic magnets . For example, the solubility and processing of organic magnets are improved due to the introduction of organic ligands and organic groups. − The quantum effect observed in a single molecular magnet and single chain magnet is promising in designing quantum computers. , The electronic spin interactions are tuned by the structural design of the organic magnet which is useful in spintronic devices .…”

“…Organic magnets 1,2 (also called molecular magnets) including single molecular magnet, 3−5 single chain magnet, 6 polyradicals, 7 and so on are molecular-based magnets which possess unpaired electrons in either p-or d-/f-orbitals that contribute to the magnetic ordering and/or magnetic spin coupling. 8,9 From the beginning of their discovery, organic magnets are expected to exhibit novel properties compared to the traditional inorganic magnets.…”

The powder X‐band electron paramagnetic resonance spectroscopy of septet pyridyl‐2,4,6‐trinitrene

“…Among all organic septet hexaradicals, aromatic trinitrenes possess the largest zero-field splitting (ZFS) parameters D S and are of considerable interest as multispin systems for exploration of organic molecular magnetism and quantum information processing. [1,2] The first X-band electron paramagnetic resonance (EPR) spectrum of septet trinitrenes has been recorded yet in 1968. [3] It was reported that photolysis of triazide 1a in frozen organic solutions leads to the appearance of numerous EPR signals indicating on the formation of septet trinitrene 2a as the major photoproduct (Scheme 1).…”