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Two binuclear Gadolinium(III) (Gd) complex [Gd2(L1)2(H2L3)2(NO3)2] (1) and [Gd2(L2)2(H2L3)2(NO3)2] (2) were obtained by using 2‐hydroxybenzaldehyde or 2‐hydroxy‐1‐naphthaldehyde, 2‐aminophenol, pyridin‐2‐ylmethanamine and Gd(NO3)3 ⋅ 6H2O in CH3CN (H2L1=(E)‐2‐((2‐hydroxybenzylidene)amino)phenol, H2L2=(E)‐1‐(((2‐hydroxyphenyl)imino)methyl)naphthalen‐2‐ol, H2L3=pyridin‐2‐ylmethanamine). Structural analysis suggests that all the ligands as protective units protect the central Gd(III) ions at the periphery. Magnetization studies exhibited magnetocaloric effect of 14.45 J ⋅ kg−1 ⋅ K−1 at 4 K under ΔH=7 T for complex 1 and 12.69 J ⋅ kg−1 ⋅ K−1 at 2 K under ΔH=7 T for complex 2. In complexes 1 and 2, although the coordination configurations are the same, the significant difference in MCE may be due to the adjustments of the peripheral ligands leading to changes in the coordination field strength. The electron affinity of the ligands can impact the interaction between the ligands and Gd(III) ions. [ABSTRACT FROM AUTHOR]

The title compound, C 48 H 42 N 3 O 18 P 3 , achieved in a two-step synthesis, comprises a cyclo-triphosphazene core and six 4-meth-oxy-carbonyl-phen-oxy groups. Each P atom is attached to two substituents located up and down with respect to the plane of the phosphazene ring, the central P 3 N 3 ring having a twist-boat conformation. The three O/P/O planes and five of the six benzene rings are nearly perpendicular to the mean plane through the phosphazene ring [dihedral angles = 82.98 (8)-88.92 (8)°], while the remaining benzene ring forms a dihedral angle of 25.72 (7)°. The crystal packing is stabilized by van der Waals inter-actions only.

In the title compound, C60H54N3O18P3, the central phosphazene ring is essentially planar, with an r.m.s. deviation of the six fitted atoms of 0.068 Å. The P-N bond lengths are within the narrow range 1.575 (2)-1.585 (2) Å, indicating the electrons are delocalized within the ring. The two ethenyl benzoate substituents on each P atom are located up and down with respect to the plane of the central P3N3 ring. The atoms of two terminal propenyl groups are disordered over two sets of sites, with refined site-occupancy ratios of 0.249 (12):0.751 (12) and 0.476 (9):0.524 (9). No intermolecular interactions are observed.