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Comprehensive Summary: Precise modulation of the magnetic anisotropy of metal ions remains highly important for the development of high–performance single‐molecule magnets (SMMs). We herein reported the synthetic, structural, spectral, magnetic, and computational studies on four mononuclear CoII complexes in a distorted octahedral environment. The change of the organosulfonate anions triggers significant modification of the distorted octahedral CoN6 coordination sphere, which enables us to tackle the influence of the structural distortion on the magnetic anisotropy in these complexes. Magnetic measurements revealed that the four complexes possess easy–plane magnetic anisotropy with large and positive zero‐field splitting parameters, which decrease with the increasing distortion of the pseudo–octahedral CoII coordination geometry. This correlation was further confirmed by high–frequency/–field EPR (HF–EPR) spectra and theoretical calculations. Dynamic magnetic susceptibility measurements indicate that these complexes both exhibit slow magnetic relaxation under an external dc field, indicating the field‐induced single‐ion magnets (SIMs) of the four complexes. These results indicate that structural distortion plays an important role in the magnetic anisotropy of CoII complexes and should be carefully considered in the design of molecular complexes with high magnetic anisotropy. [ABSTRACT FROM AUTHOR]

A new free carbon radical was obtained in a microwave‐assisted solvothermal reaction of the primary amine (1‐methyl‐1H‐benzo[d]imidazol‐2‐yl)methanamine with FeCl3⋅6 H2O in methanol at 140 °C. Through a combination of crystallography and electrospray ionization mass spectrometry, the reaction process was studied. The longest domino reaction includes 14 steps and forms up to 12 new covalent bonds (9 C−N and 3 C−C bonds) and 3 five‐membered heterocycles. For the first time, the homolytic cleavage of a C−O bond was used to synthesize a triarylmethyl radical. A free carbon radical was obtained in a domino reaction of a primary amine with FeCl3⋅6 H2O in methanol under solvothermal conditions. In this process, which was studied by crystallography and ESI mass spectrometry, the longest domino reaction features 14 steps, and methanol is sequentially activated; in addition, the homolytic cleavage of a C−O bond is proposed. [ABSTRACT FROM AUTHOR]

The largest Ln-Fe metal cluster [Gd12Fe14(μ3-OH)12(μ4-OH)6(μ4-O)12(TEOA)6(CH3COO)16(H2O)8]⋅(CH3COO)2(CH3CN)2⋅(H2O)20 ( 1) and the core-shell monodisperse metal cluster of 1 a@SiO2 ( 1 a=[Gd12Fe14(μ3-OH)12(μ4-OH)6(μ4-O)12(TEOA)6(CH3COO)16 (H2O)8]2+) were prepared. Experimental and theoretical studies on the magnetic properties of 1 and 1 a@SiO2 reveal that encapsulation of one cluster into one silica nanosphere not only effectively decreases intermolecular magnetic interactions but also significantly increases the zero-field splitting effect of the outer layer Fe3+ ions. [ABSTRACT FROM AUTHOR]

Magnetic anisotropy is the key element in the construction of single-ion magnets, a kind of nanomagnets for high-density information storage. This works describes an unusual large easy-plane magnetic anisotropy (with a zero-field splitting parameter D of +40.2 cm−1), mainly arising from the second-order spin-orbit coupling effect in a trigonal-planar CoII complex [Li(THF)4][Co(NPh2)3], revealed by combined studies of magnetism, high frequency/field electron paramagnetic resonance spectroscopy, and ab initio calculations. Meanwhile, the field-induced slow magnetic relaxation in this complex was mainly attributed to the Raman process. [ABSTRACT FROM AUTHOR]

Two polymorphs of supramolecular isomers, a discrete dimer and a zig-zag chain, having the same chemical composition, [Mn(Hbit)Cl2] (Hbit=1-methyl-2-(1H-1,2,3-triazol-4-yl)-1H-benzo[d]imidazole), were obtained solvothermally in a one-pot synthesis. The isomers differ in a number of ways: orange blocks versus pale-yellow needles, triclinic P1 versus orthorhombic Pbcn, double µ2-Cl versus alternate single and triple µ2-Cl, coordination number 5 versus 6, and antiparallel versus parallel near-neighbor orientation of Hbit. The packing in each case is driven by the supramolecular interactions, H-bonds (N--H…Cl, C--H…Cl) and π…π overlaps, calculated to be in the range 20-36 kcalmol-1. Calculations gave a difference of only 2 kcalmol-1 in favor of the dimer, which confirms with the observation of principally the dimer at short reaction time. ESI-MS spectra of the dissolved crystals reveal the same fragments with similar distributions. The presence of two fragments at m/z 286.96 [MnIV(Hbit)Cl-2H]+ and 323.94 [MnIII (Hbit)Cl2]+ indicates that [Mn(Hbit)Cl2] is the building unit in both cases; thus, the different orientations of the ligands lead to the two polymorphs stabilized by the respective supramolecular interactions. Importantly, the chain form represents the first example with alternate single and triple µ2-Cl bridges. The magnetic interactions are weakly antiferromagnetic in both cases, with J in the range 0.07-0.34 cm-1; however, high-field EPR analysis reveals moderate magneto-anisotropy with D=0.26(1) cm-1, E=0.06(1) cm-1 and D=0.17(1) cm-1, E=0.03(1) cm-1, respectively. [ABSTRACT FROM AUTHOR]

Domino Reactions. In their Communication on page 3748 ff., M.‐H. Zeng et al. describe the synthesis of a free carbon radical through the domino reaction of a primary amine with FeCl3⋅6 H2O in methanol under solvothermal conditions. [ABSTRACT FROM AUTHOR]

Magnetic anisotropy is the key element in the construction of single-ion magnets, a kind of nanomagnets for high-density information storage. This works describes an unusual large easy-plane magnetic anisotropy (with a zero-field splitting parameter D of +40.2 cm−1), mainly arising from the second-order spin-orbit coupling effect in a trigonal-planar CoII complex [Li(THF)4][Co(NPh2)3], revealed by combined studies of magnetism, high frequency/field electron paramagnetic resonance spectroscopy, and ab initio calculations. Meanwhile, the field-induced slow magnetic relaxation in this complex was mainly attributed to the Raman process. [ABSTRACT FROM AUTHOR]