Co(bpb) [bpbH2is N,N′-o-phenylenebis(pyridine-2-carboxamide) ,C18H12N4O2] complex has active axial sites like a porphyrin complex. We studied the coordination of azide ion(N3-) to Co(bpb) in binary methanol-water mix...Co(bpb) [bpbH2is N,N′-o-phenylenebis(pyridine-2-carboxamide) ,C18H12N4O2] complex has active axial sites like a porphyrin complex. We studied the coordination of azide ion(N3-) to Co(bpb) in binary methanol-water mixtures by spectrophotometric method at the temperature range of 283-303 K. From the temperature dependence of the rate constant,activation parameters(Ea,ΔH,ΔS,and ΔG) were obtained. An isokinetic temperature at about 302 K was observed at which the formation rate of Co(bpb) -N3-was more or less independent of the solvent composition. The resulting ΔH against TΔS plot showed a good linear correlation,indicating the existence of enthalpy-entropy compensation in azide complexation process. Under optimum conditions and based on the absorbance of Co(bpb) -N3-produced through complex formation,a spectrophotometric method for the determination of N 3-in solution was developed. A linear relationship between the absorbance and N3-concentration was obtained in the range of(0.85-5.00) × 10-4 mol·L-1(3.6-21.0 μg·mL-1) . The detection limit was 2.5×10-5 mol·L-1(1.0 μg·mL-1) . The proposed method was applied to the determination of N3-anion in real water samples.展开更多
Two new mononuclear Mn ￡"complexes Mn ￡¨phen￡(c)￡2￡¨N￡3￡(c)￡2￡¨￡±￡(c)andMn ￡¨phen￡(c)￡2￡¨N￡3￡(c)￡¨H￡2O￡(c)ClO4·H2 O￡¨￡2￡(c)have been synthesized...Two new mononuclear Mn ￡"complexes Mn ￡¨phen￡(c)￡2￡¨N￡3￡(c)￡2￡¨￡±￡(c)andMn ￡¨phen￡(c)￡2￡¨N￡3￡(c)￡¨H￡2O￡(c)ClO4·H2 O￡¨￡2￡(c)have been synthesized and structura lly characterized,where phen is ￡±￡?￡±￡°￡-phenanthroline￡(r)Complex1crystallizes in theP1pace group,with lattice parameters a￡1/2￡?￡(r)￡±￡?￡?￡?￡¨￡2￡(c)|!￡?b￡1/2￡±￡±￡(r)￡±￡2￡±￡?￡¨￡2￡(c)|!￡?c￡1/2￡±￡2￡(r)6￡?￡?￡±￡¨￡2￡(c)|!￡?|á￡1/2￡?￡3￡(r)￡μ￡μ￡?￡¨￡3￡(c)??￡?|?￡1/2￡?￡2￡(r)28￡*￡¨￡3￡(c)??￡?|?￡1/2￡*￡3￡(r)6￡¨￡3￡(c)??￡?V￡1/2￡±￡°￡1￡2￡(r)￡*￡¨￡′￡(c)|!￡3￡?Dc￡1/2￡±￡(r)￡μ￡±￡?Mg ?¤m￡-￡3￡?Z ￡1/22,F(000￡(c)￡1/2￡μ￡±￡°￡?R￡±￡1/2￡°￡(r)￡°￡?￡2￡°￡?w R￡2￡1/2￡°￡(r)0958(based on F￡2 ￡(c)￡?S￡1/2￡°￡(r)￡1￡?￡±￡(r)Complex2crystallizes in theP1space group,with lattice parameters a￡1/2￡?￡(r)￡?￡μ￡′￡3￡¨￡2￡(c)|!￡?b￡1/2￡?￡(r)￡1￡*￡?￡*￡¨￡2￡(c)|!￡?c￡1/2￡±￡*￡(r)5915￡¨￡′￡(c)|!￡?|á￡1/2￡1￡3￡(r)￡3￡1￡1￡¨￡3￡(c)??￡?|?￡1/2￡±￡°￡2￡(r)￡?￡°￡?￡¨￡3￡(c)??￡?|?￡1/2￡±￡°￡?￡(r)23￡′￡¨￡3￡(c)??￡?V￡1/2￡±￡2￡?￡?￡(r)￡*￡¨￡′￡(c)? ￡3 ￡?Dc￡1/2￡±￡(r)￡μ￡μ￡2Mg ?¤m￡-￡3￡?Z ￡1/2￡2￡?F￡¨￡°￡°￡°￡(c)￡1/2606,R!? ￡1/2￡°￡(r)067￡2￡?w R ￡2 ￡1/2￡°￡(r)1781(based on F2 ￡(c)￡?S￡1/2￡±￡(r)￡°￡′￡*￡(r)In complex1,the Mn atom is coordinated by six nit rogen atoms of two phen molecules and two N 3- ions with the Mn￡-N distances ranging from ￡2￡(r)￡±￡′￡2￡¨￡′￡(c)to ￡2￡(r)318(4￡(c)|!￡(r)The coordinated phen molecules of the adjacent Mn ￡¨phen￡(c) ￡2 ￡¨N ￡3 ￡(c) 2 moieties experienceπ-πstacking which is responsible for th e crystal packing￡(r)In complex2,the Mn atom is coordinated by five ni trogen atoms of two phen molecules an d one N 3- ion with the Mn￡-N distances ranging from ￡2￡(r)￡±￡μ￡2￡¨￡μ￡(c)to ￡2￡(r)291(5￡(c)|!￡(r)The approximately octahedral environment was completed by the oxygen atom of the coordinated water molecule with the Mn?O distance of ￡2￡(r)￡±￡?￡°￡¨￡μ￡(c)?￡(r)The hydrate water molecule is hydrogen-bonded to one of the O ato ms of free ClO ￡′￡- anion￡(r)展开更多
Certain N-cyanoalkyl-functionalized imidazolium halide salts unexpectedly undergo nitrile hydrolysis to amides, as well as dipolar cycloaddition to tetrazoles when eluted on azide anion exchanged resin.
基金supported by the Tarbiat Modares University Research Council.
文摘Co(bpb) [bpbH2is N,N′-o-phenylenebis(pyridine-2-carboxamide) ,C18H12N4O2] complex has active axial sites like a porphyrin complex. We studied the coordination of azide ion(N3-) to Co(bpb) in binary methanol-water mixtures by spectrophotometric method at the temperature range of 283-303 K. From the temperature dependence of the rate constant,activation parameters(Ea,ΔH,ΔS,and ΔG) were obtained. An isokinetic temperature at about 302 K was observed at which the formation rate of Co(bpb) -N3-was more or less independent of the solvent composition. The resulting ΔH against TΔS plot showed a good linear correlation,indicating the existence of enthalpy-entropy compensation in azide complexation process. Under optimum conditions and based on the absorbance of Co(bpb) -N3-produced through complex formation,a spectrophotometric method for the determination of N 3-in solution was developed. A linear relationship between the absorbance and N3-concentration was obtained in the range of(0.85-5.00) × 10-4 mol·L-1(3.6-21.0 μg·mL-1) . The detection limit was 2.5×10-5 mol·L-1(1.0 μg·mL-1) . The proposed method was applied to the determination of N3-anion in real water samples.
文摘Two new mononuclear Mn ￡"complexes Mn ￡¨phen￡(c)￡2￡¨N￡3￡(c)￡2￡¨￡±￡(c)andMn ￡¨phen￡(c)￡2￡¨N￡3￡(c)￡¨H￡2O￡(c)ClO4·H2 O￡¨￡2￡(c)have been synthesized and structura lly characterized,where phen is ￡±￡?￡±￡°￡-phenanthroline￡(r)Complex1crystallizes in theP1pace group,with lattice parameters a￡1/2￡?￡(r)￡±￡?￡?￡?￡¨￡2￡(c)|!￡?b￡1/2￡±￡±￡(r)￡±￡2￡±￡?￡¨￡2￡(c)|!￡?c￡1/2￡±￡2￡(r)6￡?￡?￡±￡¨￡2￡(c)|!￡?|á￡1/2￡?￡3￡(r)￡μ￡μ￡?￡¨￡3￡(c)??￡?|?￡1/2￡?￡2￡(r)28￡*￡¨￡3￡(c)??￡?|?￡1/2￡*￡3￡(r)6￡¨￡3￡(c)??￡?V￡1/2￡±￡°￡1￡2￡(r)￡*￡¨￡′￡(c)|!￡3￡?Dc￡1/2￡±￡(r)￡μ￡±￡?Mg ?¤m￡-￡3￡?Z ￡1/22,F(000￡(c)￡1/2￡μ￡±￡°￡?R￡±￡1/2￡°￡(r)￡°￡?￡2￡°￡?w R￡2￡1/2￡°￡(r)0958(based on F￡2 ￡(c)￡?S￡1/2￡°￡(r)￡1￡?￡±￡(r)Complex2crystallizes in theP1space group,with lattice parameters a￡1/2￡?￡(r)￡?￡μ￡′￡3￡¨￡2￡(c)|!￡?b￡1/2￡?￡(r)￡1￡*￡?￡*￡¨￡2￡(c)|!￡?c￡1/2￡±￡*￡(r)5915￡¨￡′￡(c)|!￡?|á￡1/2￡1￡3￡(r)￡3￡1￡1￡¨￡3￡(c)??￡?|?￡1/2￡±￡°￡2￡(r)￡?￡°￡?￡¨￡3￡(c)??￡?|?￡1/2￡±￡°￡?￡(r)23￡′￡¨￡3￡(c)??￡?V￡1/2￡±￡2￡?￡?￡(r)￡*￡¨￡′￡(c)? ￡3 ￡?Dc￡1/2￡±￡(r)￡μ￡μ￡2Mg ?¤m￡-￡3￡?Z ￡1/2￡2￡?F￡¨￡°￡°￡°￡(c)￡1/2606,R!? ￡1/2￡°￡(r)067￡2￡?w R ￡2 ￡1/2￡°￡(r)1781(based on F2 ￡(c)￡?S￡1/2￡±￡(r)￡°￡′￡*￡(r)In complex1,the Mn atom is coordinated by six nit rogen atoms of two phen molecules and two N 3- ions with the Mn￡-N distances ranging from ￡2￡(r)￡±￡′￡2￡¨￡′￡(c)to ￡2￡(r)318(4￡(c)|!￡(r)The coordinated phen molecules of the adjacent Mn ￡¨phen￡(c) ￡2 ￡¨N ￡3 ￡(c) 2 moieties experienceπ-πstacking which is responsible for th e crystal packing￡(r)In complex2,the Mn atom is coordinated by five ni trogen atoms of two phen molecules an d one N 3- ion with the Mn￡-N distances ranging from ￡2￡(r)￡±￡μ￡2￡¨￡μ￡(c)to ￡2￡(r)291(5￡(c)|!￡(r)The approximately octahedral environment was completed by the oxygen atom of the coordinated water molecule with the Mn?O distance of ￡2￡(r)￡±￡?￡°￡¨￡μ￡(c)?￡(r)The hydrate water molecule is hydrogen-bonded to one of the O ato ms of free ClO ￡′￡- anion￡(r)
基金supported by the US Air Force Office of Scientific Research (F49550-10-1-0521)
文摘Certain N-cyanoalkyl-functionalized imidazolium halide salts unexpectedly undergo nitrile hydrolysis to amides, as well as dipolar cycloaddition to tetrazoles when eluted on azide anion exchanged resin.
