Lanthanide complexes Ln(L1)(HL1) (Ln = Lu, Yb, Er, Gd, Eu, Sm) and Ln(L2)(HL2) (Ln = Lu, Yb, Gd, Eu) with 2-(tosylamino)-benzylidene-N-(aryloyl)hydrazones (H2L1, aryloyl = 2-hydroxybenzoyl; ...H2L2, aryloyl = isonicotinoyl) were obtained with the aim to explore them as new luminescent materials. They were found to form monomeric species independently on the aryloyl group, and their crystal structures were determined from single-crystal X-ray data (Yb(L2)(HL2)·0.5(C2H5OH)), as well as from powder X-ray data by Rietveld refinement (Eu(L1)(HL1)). Ytterbium complexes exhibited intense luminescence, which allowed using them in host-free organic light-emitting diodes, which demonstrated remarkable efficiency of near infrared electroluminescence (50 μW/W) at low voltage (5 V). The special mechanism of europium luminescence quenching allowed using europium complexes as luminescent thermometers, which demonstrated very high sensitivity up to 12%/K. The theory of luminescence thermometry based on a three-level system was proposed, which allowed predicting sensitivity with high accuracy (error within 20%).
The copper catalyzed reaction of N-monosubstituted hydrazones with carbon tetrabromide leads to formation of expected dibromodiazadienes and unexpected dibromostyrenes. The experimental and ...theoretical study of the reaction revealed a key role of N-centered radicals, which can eliminate aryl radicals to form the corresponding dibromostyrenes. Alternatively, the oxidation of intermediate N-centered radicals by Cu(II) results in the corresponding diazadienes. These two reaction pathways are competitive directions of the reaction. Consequently, the reaction can be useful for the synthesis of both dibromostyrenes and rare dibromodiazadienes.
The copper catalyzed reaction of N-monosubstituted hydrazones with carbon tetrabromide leads to formation of expected dibromodiazadienes and unexpected dibromostyrenes. The experimental and ...theoretical study of the reaction revealed a key role of N-centered radicals, which can eliminate aryl radicals to form the corresponding dibromostyrenes. Alternatively, the oxidation of intermediate N-centered radicals by Cu(II) results in the corresponding diazadienes. These two reaction pathways are competitive directions of the reaction. Consequently, the reaction can be useful for the synthesis of both dibromostyrenes and rare dibromodiazadienes.
Crystal structure of 1,1-diacetylferrocene dihydrazone Shikhaliyev, Namig G.; Gurbanov, Atash V.; Muzalevsky, Vasily M. ...
Acta crystallographica. Section E, Structure reports online,
08/2014, Letnik:
70, Številka:
8
Journal Article
Odprti dostop
The title compound, Fe(C
7
H
9
N
2
)
2
, crystallizes with two crystallographically independent molecules in the unit cell. These represent the chiral atropoisomers distinguished by the mutual ...arrangement of the two acetyl–hydrazone groups with a
cis
conformation of the C=N bonds. The two cyclopentadienyl (Cp) rings are planar and nearly parallel, the tilt between the two rings being 3.16 (16)° 4.40 (18)° for the second independent molecule. The conformation of the Cp rings is close to eclipsed, the twist angle being 0.1 (2)° 3.3 (2)°. The two acetyl–hydrazone substituents are also planar and are inclined at 13.99 (15)/9.17 (16)° 6.83 (17)/14.59 (15)° relative to the Cp rings. The Fe—C bond lengths range from 2.035 (3) to 2.065 (2) Å, with an average of 2.050 (3) Å 2.036 (3) to 2.069 (2), average 2.046 (3) Å, which agrees well with those reported for most ferrocene derivatives. In the crystal, the molecules form dimers
via
two strong N—H...N hydrogen bonds. The dimers are linked into a three-dimensional framework by weak N—H...N hydrogen bonds.
Crystal structure of 1,1-di-acetyl-ferrocene dihydrazone Shikhaliyev, Namig G; Gurbanov, Atash V; Muzalevsky, Vasily M ...
Acta crystallographica. Section E, Structure reports online,
2014-Aug-01, Letnik:
70, Številka:
Pt 8
Journal Article
Odprti dostop
The title compound, Fe(C7H9N2)2, crystallizes with two crystallographically independent mol-ecules in the unit cell. These represent the chiral atropoisomers distinguished by the mutual arrangement ...of the two acet-yl-hydrazone groups with a cis conformation of the C=N bonds. The two cyclo-penta-dienyl (Cp) rings are planar and nearly parallel, the tilt between the two rings being 3.16 (16)° 4.40 (18)° for the second independent mol-ecule. The conformation of the Cp rings is close to eclipsed, the twist angle being 0.1 (2)° 3.3 (2)°. The two acet-yl-hydrazone substituents are also planar and are inclined at 13.99 (15)/9.17 (16)° 6.83 (17)/14.59 (15)° relative to the Cp rings. The Fe-C bond lengths range from 2.035 (3) to 2.065 (2) Å, with an average of 2.050 (3) Å 2.036 (3) to 2.069 (2), average 2.046 (3) Å, which agrees well with those reported for most ferrocene derivatives. In the crystal, the mol-ecules form dimers via two strong N-H⋯N hydrogen bonds. The dimers are linked into a three-dimensional framework by weak N-H⋯N hydrogen bonds.
The title compound, Cu(C4H2Cl6N3)2, was obtained by the reaction of CCl3CN with ammonia in presence of CuCl. The CuII atom is located about an inversion centre. The molecule consists of three planar ...units (one central square CuN4 and two C2N3 fragments), adopting a staircase-like structure. The six-membered metallocycles have a sofa conformation with the Cu atom out of the plane of the 1,3,5-triazapentadienyl ligands by 0.246 (5) Å. The ipso-C atoms of the CCl3 substituents are slightly out of the 1,3,5-triazapentadienyl planes by 0.149 (6) and −0.106 (6) Å. The CCl3 groups of each 1,3,5-triazapentadienyl ligand are practically in the energetically favourable mutually eclipsed conformation. In the crystal, the molecules are packed in stacks along the a axis. The molecules in the stacks are held together by two additional axial Cu...Cl interactions of 3.354 (2) Å. Taking the axial Cu...Cl interactions into account, the CuII atom exhibits a distorted 4 + 2-octahedral coordination environment. The stacks are bound to each other by weak intermolecular attractive Cl...Cl 3.505 (2)–3.592 (3) Å interactions.
The title compound, Cu(C(4)H(2)Cl(6)N(3))(2), was obtained by the reaction of CCl(3)CN with ammonia in presence of CuCl. The Cu(II) atom is located about an inversion centre. The mol-ecule consists ...of three planar units (one central square CuN(4) and two C(2)N(3) fragments), adopting a staircase-like structure. The six-membered metallocycles have a sofa conformation with the Cu atom out of the plane of the 1,3,5-triaza-penta-dienyl ligands by 0.246 (5) Å. The ipso-C atoms of the CCl(3) substituents are slightly out of the 1,3,5-triaza-penta-dienyl planes by 0.149 (6) and -0.106 (6) Å. The CCl(3) groups of each 1,3,5-triaza-penta-dienyl ligand are practically in the energetic-ally favourable mutually eclipsed conformation. In the crystal, the mol-ecules are packed in stacks along the a axis. The mol-ecules in the stacks are held together by two additional axial Cu⋯Cl inter-actions of 3.354 (2) Å. Taking the axial Cu⋯Cl inter-actions into account, the Cu(II) atom exhibits a distorted 4 + 2-octa-hedral coordination environment. The stacks are bound to each other by weak inter-molecular attractive Cl⋯Cl 3.505 (2)-3.592 (3) Å inter-actions.
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