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Efficiently constructing structures with high thermal stability is a key objective in the development of energetic compounds. However, the existing synthesis processes for heat‐resistant energetic materials are frequently hampered by their complexity and low yields. This study presents a significant breakthrough in addressing these challenges. It successfully synthesizes 4‐amino‐5‐(3‐amino‐1H‐pyrazole‐4‐yl)‐2,4‐dihydro‐3H‐1,2,4‐triazol‐3‐one (APTO) using a streamlined two‐step process, achieving an impressive high yield of 87.5 %. The structure was determined through X‐ray single crystal diffraction analysis, revealing a nearly planar intramolecular structure. Hirshfeld surface analysis, weak interaction analysis, and aromaticity analysis were conducted, illustrating a substantial presence of hydrogen bonds and π ‐ π stacking interactions within and between molecules. These interactions contribute significantly to exceptional thermal stability of ATPO. Furthermore, the thermal stability of ATPO was confirmed through DSC analysis, exhibiting a decomposition temperature as high as 365.2°C. This temperature surpasses that of the heat‐resistant explosive HNS (325°C), further validating its excellent thermal stability. The construction of this conjugated structure offers valuable guidance for the future structural design of heat‐resistant energetic materials. It opens up possibilities for the development of novel compounds with improved thermal stability based on similar conjugated architectures. [ABSTRACT FROM AUTHOR]

A penta-coordinated dinuclear Zn(II) complex, [Zn2(L)(μ-PhCOO)(EtOH)] (1), and a hexa-coordinate tetranuclear Cd(II) complex, [{Cd2(L)(EtOH)(η-OAc)}2]·2CH2Cl2 (2), have been synthesized by reactions of a single-armed salamo-based ligand, H3L, and two kinds of transition metal salts, (Zn(NO3)2·6H2O and Cd(OAc)2·2H2O), respectively. Complexes 1 and 2 have been characterized by elemental analyses, single crystal X-ray diffraction, IR spectra and UV-Vis spectra. Complex 1 is composed of a totally deprotonated ligand (L)3- moiety, two Zn(II) ions, one μ-PhCOO- counter-anion and one coordinated ethanol molecule. The (L)3- unit packages two Zn(II) ions, the μ-PhCOO- counter-anion bridges two adjacent Zn(II) ions and one ethanol molecule coordinates with the Zn2 ion, so that both Zn(II) ions are penta-coordinated with slightly distorted trigonal bipyramidal configurations, and the τ5 values of Zn1 and Zn2 are 0.86 and 0.65, respectively. Complex 2 consists of two discrete and similar electroneutral tetra-nuclear units, 2 A and 2B, and two crystallized dichloromethane molecules. Each unit has a symmetric structure that is made up of two completely deprotonated ligand (L)3- moieties, four Cd(II) ions, two η-OAc- counter-anions and two coordinated ethanol molecules. Fluorescence properties and Hirshfeld surfaces analyses have been studied as well. [ABSTRACT FROM AUTHOR]

Two structurally different Cu(II) and Co(II) complexes, [Cu(L)] (1) and [Co2(L)2]⋅2CH3OH (2), constructed from a new polyhalogen-substituted unsymmetric salamo-based ligand (H2L, 4-chloro-4′-bromo-6-bromo-6′-tert-butyl-2,2′-[ethylenedioxybis(nitrilomethylidyne)]diphenol) were synthesized by wet-chemical methods. Complexes 1 and 2 were characterized through elemental analyses, IR and UV-vis spectroscopies and single crystal X-ray crystallography. In addition, the differences of the structures, electronic absorption characteristics and fluorescence property transitions from the ligand to complexes 1 and 2 were studied. The largest difference is that the ligand H2L can react with M(OAc)2 (M = Cu(II) and Co(II)) to give two complexes with distinct structures and behaviors. There are two chemically identical but crystallographically independent structural units (molecules A and B) in 1. Moreover, each Cu(II) ion (Cu1 or Cu2) is four-coordinate and possesses a square planar geometry, but both Co(II) ions of 2 are bridged by phenoxide ions and possess five-coordinate trigonal bipyramidal configurations. At the same time, Hirshfeld surface analyses showed there are short-range interaction features from the ligand to complexes 1 and 2, the O···H/H···O interactions of the ligand are significantly stronger than those of 1 and 2. [ABSTRACT FROM AUTHOR]

Two dinuclear Ni (II) and Zn (II) salamo‐type complexes, [Ni2(L)(μ‐OAc)(MeOH)]·2CHCl3 (1) and [{Zn2(L)(μ‐OMe)}3]·3CHCl3·MeOH (2), have been successfully synthesized by wet‐chemical method and characterized by elemental analyses, IR spectra, UV–Vis spectra and single crystal X‐ray diffraction. Complex 1 consists of two closely related dinuclear units 1A and 1B, and complex 2 consists of three closely related dinuclear units 2A, 2B and 2C. The five units are unique example of crystallographically independent but chemically identical molecules. The Ni (II) atoms of complex 1 are located in the N2O4 coordination cavities, possessing six‐coordinated distorted octahedral geometries, but all Zn (II) atoms in complex 2 are located in the N2O3 coordination cavities, possessing five‐coordinated distorted square‐pyramid and triangular bipyramid geometries, the geometries about the Zn (II) atoms (Zn3 and Zn6) that obtain in 2B and 2C where τ5 is very close to 0.500, which is τ5Zn3 = 0.5006 and τ5Zn6 = 0.4941, respectively. The interactions were quantitatively determined by Hirshfeld surfaces analyses. Significantly, fluorescence properties were also investigated. [ABSTRACT FROM AUTHOR]

Two hetero‐bimetallic [Zn(II)2M(II)] (M = Ca and Sr) complexes [Zn2Ca(L)(OAc)2] (1) and [Zn2Sr(L)(OAc)2] (2) with a novel asymmetrical bis(salamo)‐type tetraoxime ligand (H5L) were designed and synthesized, and characterized by elemental analyses, FT‐IR spectra, UV–vis absorption spectra, Density Functional Theory (DFT) calculation, Hirshfeld surface analyses and X‐ray single crystal diffractions. Compared with the symmetric bis(salamo)‐type ligands, the ligand H5L and its [Zn(II)2M(II)] (M = Ca and Sr) asymmetrical bis(salamo)‐type complexes synthesized for the first time in this paper have more novel structures and better properties. The results of ultraviolet titration show that the coordination ratio of ligand, alkaline earth metal and transition metal is 1:1:2. Complexes 1 and 2 have good luminescent properties and obvious antimicrobial activities. [ABSTRACT FROM AUTHOR]

• A salamo‐like oligo(N,O-donor) ligand H3L has been synthesized. • Unusual di-nuclear Mn(III) and tetra-nuclear Cd(II) complexes have been successfully self-assembled. • The hexa-coordinated Mn(III) and Cd(II) atoms in complexes 1 & 2 form slightly distorted octahedral geometries. • Theoretical calculations and fluorescence properties of H3L and complexes 1 and 2 were also investigated. The self-assembled di-nuclear Mn(III) & tetra-nuclear Cd(II) salamo-like oligo(N,O-donor) complexes, [Mn 2 (L) 2 (CH 3 OH) 2 ]·4CH 3 OH (1) and [Cd 4 (L) 2 (η -OAc) 2 (CH 3 OH) 2 ] (2) have been constructed successfully applying the measure of solvent evaporation and characterized structurally by X-ray diffraction analyses of single crystal, IR & UV visible analyses. The single crystals of the salamo-like oligo(N,O-donor) compound H 3 L have been obtained by wet-chemical technique, its established structure is H 3 L∙CH 3 OH. The structure of complex 1 is centrally symmetrical, and both Mn(III) atoms are hexa-coordination and have slightly distorted octahedral geometries. There are two sets of intermolecular H-bonding interactions which are connected with adjacent units of the Mn(III) complexes and form a two-dimensional network structure. For the complex 2 , all of the Cd(II) atoms are also hexa-coordination and possess slightly twisted octahedral configurations. And five groups of intermolecular H-bonding interactions form a honeycomb shaped three-dimensional supramolecular structure. Additionally, the intermolecular interactions of H 3 L, complexes 1 and 2 have been quantified by Hirshfeld surface analysis for further study. Fluorescence emission spectra of H 3 L, complexes 1 and 2 were also investigated. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] Three new Co(II) complexes containing half-salamo type ligand HL viz. [Co(L)Cl] (1), [Co(L)(NO 3)] (2) and [Co(L)(NCS)] (3) were synthesized and characterized by single crystal X-ray diffraction. The results showed that the central Co(II) atoms in mononuclear complexes 1 – 3 are all located in the N 3 O cavity of the deprotonated ligand (L)− unit, while coordinated with different counteranions. The presence of counteranions in complexes 1 – 3 are Cl−, NO 3 − and NCS−, respectively. The spectral properties of these complexes were investigated in detail. In addition, the structural descriptions were corroborated with theoretical calculations. The Hirshfeld surface analysis combined with 2D fingerprint plots revealed the short-range intermolecular interactions of these complexes. [ABSTRACT FROM AUTHOR]

• A new kind of single‐armed salamo‐type ligand H 3 L and two corresponding Zn(II) complexes have been synthesized. • All of the Zn(Ⅱ) atoms in complexes 1 and 2 are penta-coordinated, highly distinct configurations are obtained because of the introduction of two kinds of counter-anions. • Fluorescence properties of H 3 L and complexes 1 and 2 were also investigated. Di- and tetra-nuclear Zn(II) complexes, [Zn 2 (L)(µ -OAc)(CH 3 OH)]·CH 3 OH (1) and [Zn 4 (L) 2 (OMe) 2 ]·2CH 3 COCH 3 ·CH 3 OH (2) have been successfully self-assembled by the reaction of a single‐armed salamo‐type ligand (H 3 L), Zn(OAc) 2 ·2H 2 O and Zn(NO 3) 2 ·6H 2 O, respectively. In the ligand H 3 L, tetradentate N 2 O 2 donor part of pocket I and NO 2 donor part of pocket II are designed to bond Zn(II) atoms, then unusually structural complexes were obtained by counteranion-driven self-assembled. Both complexes 1 and 2 are characterized by elemental analyses, IR spectra, UV-Vis spectra and single crystal X-ray diffraction. All of the Zn(II) atoms in complexes 1 and 2 are penta-coordinated, but highly distinct configurations are obtained because of the introduction of two kinds of counter-anions. In complex 1 , μ- OAc− counter-anion connects the two Zn(II) atoms in one ligand. In complex 2 , μ- OMe− counter-anions link the Zn(II) atoms within two ligand molecules and the structure of complex 2 is more complicated. What's more, in complex 1 , all Zn(II) atoms have the geometries of distorted trigonal bipyramid, while in complex 2 , all Zn(II) atoms have the geometries of distorted square pyramid. There are obvious π···π stacking interactions existing in complexes 1 and 2 , which are quantitatively valued by Hirshfeld surfaces analyses. Fluorescence properties are also investigated. Di- and tetra-nuclear Zn(II) complexes, [Zn 2 (L)(µ -OAc)(CH 3 OH)]·CH 3 OH (1) and [Zn 4 (L) 2 (OMe) 2 ]·2CH 3 COCH 3 ·CH 3 OH (2) have been successfully synthesized and structurally characterized. The fluorescence properties were also investigated. [Display omitted] [ABSTRACT FROM AUTHOR]

Three novel N 4 -cavity Cu(II), Ni(II) and Zn(II) complexes were successfully synthesized via the reactions of a novel pyridine-containing N 4 -cavity bisoxime ligand L. All three complexes are monoclinic systems. Complexes 2 and 3 form centrosymmetric helical molecules. Complexes 1 – 3 have been characterized by elemental analysis, IR, UV–Vis spectroscopy and single crystal X-ray crystallography. In addition, supramolecular interactions, Hirshfeld surface analysis to analyze the crystal properties have been studied. [Display omitted] • A novel ligand L with N4 cavity was synthesized and characterized. • Three excess metal single crystals were synthesized via the ligand L. • Hirshfeld surface analysis was performed on single crystals. Three novel N 4 -cavity Cu(II), Ni(II) and Zn(II) mononuclear complexes, [Cu(L)(NO 3) 2 ][Cu(L)(NO 3)]NO 3 (1) [Ni(L)(NO 3) 2 ] (2) and [Zn(L)(NO 3) 2 ] (3) were successfully synthesized via the reactions of a pyridine-containing N 4 -cavity bisoxime ligand L (L = 2,2′-[Ethylenedioxobis(azetidinyl)]pyridine) with Cu(II), Ni(II) and Zn(II) nitrates, respectively. Complexes 1 – 3 were characterized via elemental analysis, IR, UV–Vis spectra and X-ray crystallography. All three complexes are monoclinic systems, containing one M(II) atom and one (L) ligand moiety. Complexes 2 and 3 form centrosymmetric molecules. In addition, supramolecular interactions, Hirshfeld surface analysis were used to analyze the crystal properties that have been studied. [ABSTRACT FROM AUTHOR]

A new pyridine-decorated half-salamo-like ligand (HL) was designed and synthesized. Three novel anion-dependent Cu(II) complexes [Cu(L)Cl]·CH 3 OH (1), [Cu(L)Br] (2) and [Cu(L)(NO 3)] (3) have been synthesized and characterized structurally. Furthermore, DFT calculations were investigated in the complexes 1 , 2 and 3. Paradoxically, the fluorescence intensities of these Cu(II) complexes are significantly increased compared to the ligand. [Display omitted] • A new pyridine-decorated half-salamo-like ligand was synthesized. • Three anion-dependent Cu(II) complexes 1 , 2 and 3 have been synthesized and characterized structurally. • The fluorescence intensities of these Cu(II) complexes are significantly increased compared to the ligand. A new pyridine-decorated half-salamo-like ligand (HL) was designed and synthesized by a one-pot method. Based on this ligand, the single crystals of three anion-dependent Cu(II) complexes [Cu(L)Cl]·CH 3 OH (1), [Cu(L)Br] (2) and [Cu(L)(NO 3)] (3) have been cultivated successfully and the structural features were determined by single crystal X-ray diffraction analyses. The results showed that the complexes 1 , 2 and 3 have homologous mononuclear structures, in which the five-coordinated Cu(II) atom is not only surrounded by the N 3 O cavity of the ligand (L)- unit, but also coordinated with Cl−, Br− and NO 3 − as auxiliary coordination, respectively. The ligand HL and the complexes 1 , 2 and 3 were characterized via elemental analyses, IR and UV–Vis spectroscopy. The short-range interactions of the complexes 1 , 2 and 3 were investigated by Hirshfeld surfaces analyses. Furthermore, DFT calculations were investigated in the complexes 1 , 2 and 3. Paradoxically, the fluorescence intensities of these Cu(II) complexes are significantly increased compared to the ligand. [ABSTRACT FROM AUTHOR]

The Cu(II) and Ni(II) complexes self-assembled from a novel salamo-like ligand H 2 L containing double terminal pyridine groups, [Cu(LH)]NO 3 ⋅CH 3 CH 2 OH and [{Ni(L)} 2 ] n ·nC 5 H 5 N⋅nCH 3 COCH 3 were designed and synthesized. The Cu(II) atom is located at the N 2 O 2 cavity of the deprotonation ligand (L)2− moiety, but the N atoms of the terminal pyridine groups of the ligand (L)2− moiety is not involved in the coordination, and forms a four-coordinated twisted quadrilateral geometry. While the Ni(II) atom (Ni1 or Ni2) is sited in the N 2 O 2 cavity of the deprotonation ligand (L)2− moiety and forms a plane, the terminal pyridine N atoms from the two adjacent [Ni(L)] moieties also coordinated with the Ni(II) atom in the axial positions to form a slightly distorted octahedral geometry with six-coordination. The benzene and pyridine rings of the ligand (L)2− moiety are rotated and create an angle, result to form a chiral MOFs using an achiral ligand (L)2− moiety. • Containing double terminal pyridine groups novel salamo-like ligand was synthesized. • The structurally different Cu(II) and Ni(II) complexes were self-assembled. • The Cu(II) and Ni(II) complexes have huge structural differences. • Compared with the Cu(Ⅱ) complex, the Ni(Ⅱ) complex has better thermal stability. A novel structurally characterized salamo-like ligand H 2 L contained double terminal pyridine groups was designed and synthesized. The single crystals of the Cu(II) and Ni(II) complexes are grown up through coordination of H 2 L with Cu(II) and Ni(II) ions, respectively, determined as [Cu(LH)]NO 3 ⋅CH 3 CH 2 OH and [{Ni(L)} 2 ] n ·n3C 5 H 5 N·nCH 3 COCH 3. The Cu(II) atom is located at the N 2 O 2 cavity of the deprotonation ligand (L)2− moiety, but the N atoms of the terminal pyridine groups of the ligand (L)2− moiety is not involved in the coordination, and forms a four-coordinated twisted quadrilateral geometry. While the Ni(II) atom (Ni1 or Ni2) is sited in the N 2 O 2 cavity of the deprotonation ligand (L)2− moiety and forms a plane, the terminal pyridine N atoms from the two adjacent [Ni(L)] moieties also coordinated with the Ni(II) atom in the axial positions to form a slightly distorted octahedral geometry with six-coordination. In the formation of MOFs, the benzene and pyridine rings of the ligand (L)2− moiety are rotated and create an angle, result to form a chiral MOFs using an achiral ligand (L)2− moiety. View of MOFs in the C direction, the Ni(II) complex has four different size of apertures in its structure, and presences a large amount of protonic hydrogen. Spectroscopic analyses of H 2 L and its Cu(II) and Ni(II) complexes are performed using IR, UV–Vis and fluorescence spectroscopy. Compared with the Cu(II) complex, the Ni(II) complex has better thermal stability. The magnetic analyses were also carried out. Hirshfeld surfaces analyses are carried out to analyze various short-range interactions in H 2 L and its Cu(II) complex. [ABSTRACT FROM AUTHOR]

Three new multi-nuclear Cu(II) complexes have been successfully synthesized by the one-pot reaction of a bis(salamo)-based ligand H 3 L and different copper(II) salts and characterized structurally. • Three new multi-nuclear Cu(II) complexes have been successfully synthesized and characterized structurally. • Complex 3 is a novel penta-nuclear structure derived of the ligand (HL)2- units. • Effects of counteranions and fluorescence properties were also investigated. Three new multi-nuclear Cu(II) complexes, [Cu 4 (L) 2 (CH 3 OH) 2 ](NO 3) 2 ·2CH 3 OH (1), [Cu 4 (L) 2 (CH 3 OH)(CH 3 CN)](ClO 4) 2 ·2CH 3 OH (2) and [Cu 4 (HL) 2 (μ 2 -Cl) 2 Cl 2 (CH 3 CH 2 OH) 2 ][CuCl 2 ]·CHCl 3 (3) have been successfully synthesized by the one-pot reaction of a bis(salamo)-based ligand H 3 L with Cu(NO 3) 2 ·3H 2 O, Cu(ClO 4) 2 ·6H 2 O and CuCl 2 ·2H 2 O, respectively. Complexes 1 and 2 are monoclinic systems including four Cu(II) atoms with two completely deprotonated ligand (L)3- units, which form centrosymmetric helical molecules. Complex 3 is triclinic system including five Cu(II) atoms with two incompletely deprotonated ligand (HL)2- units, which forms an expanded structural molecule. Complexes 1 – 3 have been characterized by elemental analyses, IR, UV–Vis spectroscopy and single crystal X-ray crystallography. In addition, supramolecular interactions, Hirshfeld surfaces analyses, effects of counteranions and fluorescence properties were also investigated. [ABSTRACT FROM AUTHOR]