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Carlos Yélamos - One of the best experts on this subject based on the ideXlab platform.
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Reactivity with electrophiles of imido groups supported on trinuclear titanium systems.
Inorganic chemistry, 2013Co-Authors: Jorge Caballo, Miguel Mena, Adrián Pérez-redondo, Mariano González-moreiras, Carlos YélamosAbstract:Several trinuclear titanium complexes bearing amido μ-NHR, imido μ-NR, and nitrido μn-N ligands have been prepared by reaction of [{Ti(η(5)-C5Me5)(μ-NH)}3(μ3-N)] (1) with 1 equiv of electrophilic reagents ROTf (R = H, Me, SiMe3; OTf = OSO2CF3). Treatment of 1 with triflic acid or methyl triflate in toluene at room temperature affords the precipitation of compounds [Ti3(η(5)-C5Me5)3(μ3-N)(μ-NH)2(μ-NH2)(OTf)] (2) or [Ti3(η(5)-C5Me5)3(μ3-N)(μ-NH)(μ-NH2)(μ-NMe)(OTf)] (3). Complexes 2 and 3 exhibit a fluxional behavior in solution consisting of proton exchange between μ-NH2 and μ-NH groups, assisted by the triflato ligand, as could be inferred from a dynamic NMR spectroscopy study. Monitoring by NMR spectroscopy the reaction course of 1 with MeOTf allows the characterization of the methylamido intermediate [Ti3(η(5)-C5Me5)3(μ3-N)(μ-NH)2(μ-NHMe)(OTf)] (4), which readily rearranges to give 3 by a proton migration from the NHMe amido group to the NH imido ligands. The treatment of 1 with 1 equiv of Me3SiOTf produces the stable ionic complex [Ti3(η(5)-C5Me5)3(μ3-N)(μ-NH)2(μ-NHSiMe3)][OTf] (5) with a disposition of the nitrogen ligands similar to that of 4. Complex 5 reacts with 1 equiv of [K{N(SiMe3)2}] at room temperature to give [Ti3(η(5)-C5Me5)3(μ3-N)(μ-N)(μ-NH)(μ-NHSiMe3)] (6), which at 85 °C rearranges to the trimethylsilylimido Derivative [Ti3(η(5)-C5Me5)3(μ3-N)(μ-NH)2(μ-NSiMe3)] (7). Treatment of 7 with [K{N(SiMe3)2}] affords the Potassium Derivative [K{(μ3-N)(μ3-NH)(μ3-NSiMe3)Ti3(η(5)-C5Me5)3(μ3-N)}] (8), which upon addition of 18-crown-6 leads to the ion pair [K(18-crown-6)][Ti3(η(5)-C5Me5)3(μ3-N)(μ-N)(μ-NH)(μ-NSiMe3)] (9). The X-ray crystal structures of 2, 5, 6, and 8 have been determined.
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Cadmium and Mercury Complexes Containing Trinuclear Titanium Imido‐Nitrido Metalloligands
European Journal of Inorganic Chemistry, 2011Co-Authors: Avelino Martín, Miguel Mena, Adrián Pérez-redondo, Carlos YélamosAbstract:Several heterometallic nitrido complexes have been prepared from the reaction of the trinuclear imido-nitrido titanium complex [{Ti(η5-C5Me5)(μ-NH)}3(μ3-N)] (1) with cadmium and mercury Derivatives. Treatment of 1 with cadmium dichloride or cadmium diiodide in toluene afforded the adducts [X2Cd{(μ3-NH)3Ti3(η5-C5Me5)3(μ3-N)}] [X = Cl (2), I (3)]. Complex 2 reacted with lithium reagents [LiR] in toluene to give the cube-type Derivatives [RCd{(μ3-N)(μ3-NH)2Ti3(η5-C5Me5)3(μ3-N)}] [R = CH2SiMe3 (4), C≡CSiMe3 (5), C5H4(SiMe3) (6), N(SiMe3)2 (7)]. The amido complex 7 reacted with 1 equiv. of 1 to give the corner-shared double-cube complex [Cd{(μ3-N)(μ3-NH)2Ti3(η5-C5Me5)3(μ3-N)}2] (8) by means of bis(trimethylsilyl)amine elimination. Treatment of 1 with mercury(II) iodide in toluene gave the adduct [I2Hg{(μ3-NH)3Ti3(η5-C5Me5)3(μ3-N)}] (9), which reacted with [K{N(SiMe3)2}] to afford [Hg{(μ3-N)2Ti3(η5-C5Me5)3(μ-NH)(μ3-N)}]2 (10) through the amido mercury intermediate [{(Me3Si)2N}Hg{(μ3-N)Ti3(η5-C5Me5)3(μ-NH)2(μ3-N)}] (11). Compound 11 and the analogous alkyl Derivative [(Me3SiCH2)Hg{(μ3-N)Ti3(η5-C5Me5)3(μ-NH)2(μ3-N)}] (12) were characterised by NMR spectroscopy upon the treatment of 1 with [Hg{N(SiMe3)2}R] [R = N(SiMe3)2, CH2SiMe3]. Complex [Hg{(μ3-N)Ti3(η5-C5Me5)3(μ-NH)2(μ3-N)}2] (13), with one bridging mercury atom between two titanium trinuclear systems, was obtained upon treatment of HgI2 with the Potassium Derivative [K(μ4-N)(μ3-NH)2{Ti3(η5-C5Me5)3(μ3-N)}]2. Complexes 3, 5 and 8 were characterised by single-crystal X-ray diffraction analysis.
Adrián Pérez-redondo - One of the best experts on this subject based on the ideXlab platform.
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Reactivity with electrophiles of imido groups supported on trinuclear titanium systems.
Inorganic chemistry, 2013Co-Authors: Jorge Caballo, Miguel Mena, Adrián Pérez-redondo, Mariano González-moreiras, Carlos YélamosAbstract:Several trinuclear titanium complexes bearing amido μ-NHR, imido μ-NR, and nitrido μn-N ligands have been prepared by reaction of [{Ti(η(5)-C5Me5)(μ-NH)}3(μ3-N)] (1) with 1 equiv of electrophilic reagents ROTf (R = H, Me, SiMe3; OTf = OSO2CF3). Treatment of 1 with triflic acid or methyl triflate in toluene at room temperature affords the precipitation of compounds [Ti3(η(5)-C5Me5)3(μ3-N)(μ-NH)2(μ-NH2)(OTf)] (2) or [Ti3(η(5)-C5Me5)3(μ3-N)(μ-NH)(μ-NH2)(μ-NMe)(OTf)] (3). Complexes 2 and 3 exhibit a fluxional behavior in solution consisting of proton exchange between μ-NH2 and μ-NH groups, assisted by the triflato ligand, as could be inferred from a dynamic NMR spectroscopy study. Monitoring by NMR spectroscopy the reaction course of 1 with MeOTf allows the characterization of the methylamido intermediate [Ti3(η(5)-C5Me5)3(μ3-N)(μ-NH)2(μ-NHMe)(OTf)] (4), which readily rearranges to give 3 by a proton migration from the NHMe amido group to the NH imido ligands. The treatment of 1 with 1 equiv of Me3SiOTf produces the stable ionic complex [Ti3(η(5)-C5Me5)3(μ3-N)(μ-NH)2(μ-NHSiMe3)][OTf] (5) with a disposition of the nitrogen ligands similar to that of 4. Complex 5 reacts with 1 equiv of [K{N(SiMe3)2}] at room temperature to give [Ti3(η(5)-C5Me5)3(μ3-N)(μ-N)(μ-NH)(μ-NHSiMe3)] (6), which at 85 °C rearranges to the trimethylsilylimido Derivative [Ti3(η(5)-C5Me5)3(μ3-N)(μ-NH)2(μ-NSiMe3)] (7). Treatment of 7 with [K{N(SiMe3)2}] affords the Potassium Derivative [K{(μ3-N)(μ3-NH)(μ3-NSiMe3)Ti3(η(5)-C5Me5)3(μ3-N)}] (8), which upon addition of 18-crown-6 leads to the ion pair [K(18-crown-6)][Ti3(η(5)-C5Me5)3(μ3-N)(μ-N)(μ-NH)(μ-NSiMe3)] (9). The X-ray crystal structures of 2, 5, 6, and 8 have been determined.
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Cadmium and Mercury Complexes Containing Trinuclear Titanium Imido‐Nitrido Metalloligands
European Journal of Inorganic Chemistry, 2011Co-Authors: Avelino Martín, Miguel Mena, Adrián Pérez-redondo, Carlos YélamosAbstract:Several heterometallic nitrido complexes have been prepared from the reaction of the trinuclear imido-nitrido titanium complex [{Ti(η5-C5Me5)(μ-NH)}3(μ3-N)] (1) with cadmium and mercury Derivatives. Treatment of 1 with cadmium dichloride or cadmium diiodide in toluene afforded the adducts [X2Cd{(μ3-NH)3Ti3(η5-C5Me5)3(μ3-N)}] [X = Cl (2), I (3)]. Complex 2 reacted with lithium reagents [LiR] in toluene to give the cube-type Derivatives [RCd{(μ3-N)(μ3-NH)2Ti3(η5-C5Me5)3(μ3-N)}] [R = CH2SiMe3 (4), C≡CSiMe3 (5), C5H4(SiMe3) (6), N(SiMe3)2 (7)]. The amido complex 7 reacted with 1 equiv. of 1 to give the corner-shared double-cube complex [Cd{(μ3-N)(μ3-NH)2Ti3(η5-C5Me5)3(μ3-N)}2] (8) by means of bis(trimethylsilyl)amine elimination. Treatment of 1 with mercury(II) iodide in toluene gave the adduct [I2Hg{(μ3-NH)3Ti3(η5-C5Me5)3(μ3-N)}] (9), which reacted with [K{N(SiMe3)2}] to afford [Hg{(μ3-N)2Ti3(η5-C5Me5)3(μ-NH)(μ3-N)}]2 (10) through the amido mercury intermediate [{(Me3Si)2N}Hg{(μ3-N)Ti3(η5-C5Me5)3(μ-NH)2(μ3-N)}] (11). Compound 11 and the analogous alkyl Derivative [(Me3SiCH2)Hg{(μ3-N)Ti3(η5-C5Me5)3(μ-NH)2(μ3-N)}] (12) were characterised by NMR spectroscopy upon the treatment of 1 with [Hg{N(SiMe3)2}R] [R = N(SiMe3)2, CH2SiMe3]. Complex [Hg{(μ3-N)Ti3(η5-C5Me5)3(μ-NH)2(μ3-N)}2] (13), with one bridging mercury atom between two titanium trinuclear systems, was obtained upon treatment of HgI2 with the Potassium Derivative [K(μ4-N)(μ3-NH)2{Ti3(η5-C5Me5)3(μ3-N)}]2. Complexes 3, 5 and 8 were characterised by single-crystal X-ray diffraction analysis.
Miguel Mena - One of the best experts on this subject based on the ideXlab platform.
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Reactivity with Electrophiles of Imido Groups Supported on Trinuclear Titanium Systems
2016Co-Authors: Jorge Caballo, Miguel Mena, Mariano González-moreiras, Adrián Pérez-redondo, Carlos YélamosAbstract:Several trinuclear titanium complexes bearing amido μ-NHR, imido μ-NR, and nitrido μn-N ligands have been prepared by reaction of [{Ti(η5-C5Me5)(μ-NH)}3(μ3-N)] (1) with 1 equiv of electrophilic reagents ROTf (R = H, Me, SiMe3; OTf = OSO2CF3). Treatment of 1 with triflic acid or methyl triflate in toluene at room temperature affords the precipitation of compounds [Ti3(η5-C5Me5)3(μ3-N)(μ-NH)2(μ-NH2)(OTf)] (2) or [Ti3(η5-C5Me5)3(μ3-N)(μ-NH)(μ-NH2)(μ-NMe)(OTf)] (3). Complexes 2 and 3 exhibit a fluxional behavior in solution consisting of proton exchange between μ-NH2 and μ-NH groups, assisted by the triflato ligand, as could be inferred from a dynamic NMR spectroscopy study. Monitoring by NMR spectroscopy the reaction course of 1 with MeOTf allows the characterization of the methylamido intermediate [Ti3(η5-C5Me5)3(μ3-N)(μ-NH)2(μ-NHMe)(OTf)] (4), which readily rearranges to give 3 by a proton migration from the NHMe amido group to the NH imido ligands. The treatment of 1 with 1 equiv of Me3SiOTf produces the stable ionic complex [Ti3(η5-C5Me5)3(μ3-N)(μ-NH)2(μ-NHSiMe3)][OTf] (5) with a disposition of the nitrogen ligands similar to that of 4. Complex 5 reacts with 1 equiv of [K{N(SiMe3)2}] at room temperature to give [Ti3(η5-C5Me5)3(μ3-N)(μ-N)(μ-NH)(μ-NHSiMe3)] (6), which at 85 °C rearranges to the trimethylsilylimido Derivative [Ti3(η5-C5Me5)3(μ3-N)(μ-NH)2(μ-NSiMe3)] (7). Treatment of 7 with [K{N(SiMe3)2}] affords the Potassium Derivative [K{(μ3-N)(μ3-NH)(μ3-NSiMe3)Ti3(η5-C5Me5)3(μ3-N)}] (8), which upon addition of 18-crown-6 leads to the ion pair [K(18-crown-6)][Ti3(η5-C5Me5)3(μ3-N)(μ-N)(μ-NH)(μ-NSiMe3)] (9). The X-ray crystal structures of 2, 5, 6, and 8 have been determined
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Reactivity with electrophiles of imido groups supported on trinuclear titanium systems.
Inorganic chemistry, 2013Co-Authors: Jorge Caballo, Miguel Mena, Adrián Pérez-redondo, Mariano González-moreiras, Carlos YélamosAbstract:Several trinuclear titanium complexes bearing amido μ-NHR, imido μ-NR, and nitrido μn-N ligands have been prepared by reaction of [{Ti(η(5)-C5Me5)(μ-NH)}3(μ3-N)] (1) with 1 equiv of electrophilic reagents ROTf (R = H, Me, SiMe3; OTf = OSO2CF3). Treatment of 1 with triflic acid or methyl triflate in toluene at room temperature affords the precipitation of compounds [Ti3(η(5)-C5Me5)3(μ3-N)(μ-NH)2(μ-NH2)(OTf)] (2) or [Ti3(η(5)-C5Me5)3(μ3-N)(μ-NH)(μ-NH2)(μ-NMe)(OTf)] (3). Complexes 2 and 3 exhibit a fluxional behavior in solution consisting of proton exchange between μ-NH2 and μ-NH groups, assisted by the triflato ligand, as could be inferred from a dynamic NMR spectroscopy study. Monitoring by NMR spectroscopy the reaction course of 1 with MeOTf allows the characterization of the methylamido intermediate [Ti3(η(5)-C5Me5)3(μ3-N)(μ-NH)2(μ-NHMe)(OTf)] (4), which readily rearranges to give 3 by a proton migration from the NHMe amido group to the NH imido ligands. The treatment of 1 with 1 equiv of Me3SiOTf produces the stable ionic complex [Ti3(η(5)-C5Me5)3(μ3-N)(μ-NH)2(μ-NHSiMe3)][OTf] (5) with a disposition of the nitrogen ligands similar to that of 4. Complex 5 reacts with 1 equiv of [K{N(SiMe3)2}] at room temperature to give [Ti3(η(5)-C5Me5)3(μ3-N)(μ-N)(μ-NH)(μ-NHSiMe3)] (6), which at 85 °C rearranges to the trimethylsilylimido Derivative [Ti3(η(5)-C5Me5)3(μ3-N)(μ-NH)2(μ-NSiMe3)] (7). Treatment of 7 with [K{N(SiMe3)2}] affords the Potassium Derivative [K{(μ3-N)(μ3-NH)(μ3-NSiMe3)Ti3(η(5)-C5Me5)3(μ3-N)}] (8), which upon addition of 18-crown-6 leads to the ion pair [K(18-crown-6)][Ti3(η(5)-C5Me5)3(μ3-N)(μ-N)(μ-NH)(μ-NSiMe3)] (9). The X-ray crystal structures of 2, 5, 6, and 8 have been determined.
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Cadmium and Mercury Complexes Containing Trinuclear Titanium Imido‐Nitrido Metalloligands
European Journal of Inorganic Chemistry, 2011Co-Authors: Avelino Martín, Miguel Mena, Adrián Pérez-redondo, Carlos YélamosAbstract:Several heterometallic nitrido complexes have been prepared from the reaction of the trinuclear imido-nitrido titanium complex [{Ti(η5-C5Me5)(μ-NH)}3(μ3-N)] (1) with cadmium and mercury Derivatives. Treatment of 1 with cadmium dichloride or cadmium diiodide in toluene afforded the adducts [X2Cd{(μ3-NH)3Ti3(η5-C5Me5)3(μ3-N)}] [X = Cl (2), I (3)]. Complex 2 reacted with lithium reagents [LiR] in toluene to give the cube-type Derivatives [RCd{(μ3-N)(μ3-NH)2Ti3(η5-C5Me5)3(μ3-N)}] [R = CH2SiMe3 (4), C≡CSiMe3 (5), C5H4(SiMe3) (6), N(SiMe3)2 (7)]. The amido complex 7 reacted with 1 equiv. of 1 to give the corner-shared double-cube complex [Cd{(μ3-N)(μ3-NH)2Ti3(η5-C5Me5)3(μ3-N)}2] (8) by means of bis(trimethylsilyl)amine elimination. Treatment of 1 with mercury(II) iodide in toluene gave the adduct [I2Hg{(μ3-NH)3Ti3(η5-C5Me5)3(μ3-N)}] (9), which reacted with [K{N(SiMe3)2}] to afford [Hg{(μ3-N)2Ti3(η5-C5Me5)3(μ-NH)(μ3-N)}]2 (10) through the amido mercury intermediate [{(Me3Si)2N}Hg{(μ3-N)Ti3(η5-C5Me5)3(μ-NH)2(μ3-N)}] (11). Compound 11 and the analogous alkyl Derivative [(Me3SiCH2)Hg{(μ3-N)Ti3(η5-C5Me5)3(μ-NH)2(μ3-N)}] (12) were characterised by NMR spectroscopy upon the treatment of 1 with [Hg{N(SiMe3)2}R] [R = N(SiMe3)2, CH2SiMe3]. Complex [Hg{(μ3-N)Ti3(η5-C5Me5)3(μ-NH)2(μ3-N)}2] (13), with one bridging mercury atom between two titanium trinuclear systems, was obtained upon treatment of HgI2 with the Potassium Derivative [K(μ4-N)(μ3-NH)2{Ti3(η5-C5Me5)3(μ3-N)}]2. Complexes 3, 5 and 8 were characterised by single-crystal X-ray diffraction analysis.
Avelino Martín - One of the best experts on this subject based on the ideXlab platform.
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Cadmium and Mercury Complexes Containing Trinuclear Titanium Imido‐Nitrido Metalloligands
European Journal of Inorganic Chemistry, 2011Co-Authors: Avelino Martín, Miguel Mena, Adrián Pérez-redondo, Carlos YélamosAbstract:Several heterometallic nitrido complexes have been prepared from the reaction of the trinuclear imido-nitrido titanium complex [{Ti(η5-C5Me5)(μ-NH)}3(μ3-N)] (1) with cadmium and mercury Derivatives. Treatment of 1 with cadmium dichloride or cadmium diiodide in toluene afforded the adducts [X2Cd{(μ3-NH)3Ti3(η5-C5Me5)3(μ3-N)}] [X = Cl (2), I (3)]. Complex 2 reacted with lithium reagents [LiR] in toluene to give the cube-type Derivatives [RCd{(μ3-N)(μ3-NH)2Ti3(η5-C5Me5)3(μ3-N)}] [R = CH2SiMe3 (4), C≡CSiMe3 (5), C5H4(SiMe3) (6), N(SiMe3)2 (7)]. The amido complex 7 reacted with 1 equiv. of 1 to give the corner-shared double-cube complex [Cd{(μ3-N)(μ3-NH)2Ti3(η5-C5Me5)3(μ3-N)}2] (8) by means of bis(trimethylsilyl)amine elimination. Treatment of 1 with mercury(II) iodide in toluene gave the adduct [I2Hg{(μ3-NH)3Ti3(η5-C5Me5)3(μ3-N)}] (9), which reacted with [K{N(SiMe3)2}] to afford [Hg{(μ3-N)2Ti3(η5-C5Me5)3(μ-NH)(μ3-N)}]2 (10) through the amido mercury intermediate [{(Me3Si)2N}Hg{(μ3-N)Ti3(η5-C5Me5)3(μ-NH)2(μ3-N)}] (11). Compound 11 and the analogous alkyl Derivative [(Me3SiCH2)Hg{(μ3-N)Ti3(η5-C5Me5)3(μ-NH)2(μ3-N)}] (12) were characterised by NMR spectroscopy upon the treatment of 1 with [Hg{N(SiMe3)2}R] [R = N(SiMe3)2, CH2SiMe3]. Complex [Hg{(μ3-N)Ti3(η5-C5Me5)3(μ-NH)2(μ3-N)}2] (13), with one bridging mercury atom between two titanium trinuclear systems, was obtained upon treatment of HgI2 with the Potassium Derivative [K(μ4-N)(μ3-NH)2{Ti3(η5-C5Me5)3(μ3-N)}]2. Complexes 3, 5 and 8 were characterised by single-crystal X-ray diffraction analysis.
H. Drulis - One of the best experts on this subject based on the ideXlab platform.
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Optical properties of chromium(III) in trigonal KAl(MoO4)2 and monoclinic NaAl(MoO4)2 hosts
Journal of Luminescence, 2000Co-Authors: Krzysztof Hermanowicz, M. Mączka, Przemysław J. Dereń, Jerzy Hanuza, Wieslaw Strek, H. DrulisAbstract:Abstract Infrared, Raman, absorption, excitation and emission spectra as well as electron spin resonance spectra were measured for KCrxAl1−x(MoO4)2 and NaCrxAl1−x(MoO4)2 crystals (x varies from 0% to 2%) at temperatures ranging from 15 to 300 K. A very rich vibronic structure of the emission band was explained and assigned to the respective vibrational modes. One Cr3+ center characterized by 2.1 and 2.8 ms lifetimes (at 15 K) for the sodium and Potassium Derivative, respectively, for the 2E→4A2 transition was identified for both the crystals. The phase transition from trigonal to monoclinic space group was discovered at about 60 K for KAl(MoO4)2 : Cr3+ crystal. The local structure of the Cr3+ surrounding is discussed in terms of the spectroscopic results and the crystal field parameters are derived for both the materials.