Two tetrathiafulvalene-calix[4]arene assemblies (TTF-calix-1 and TFF-calix-2) have been synthesized by the click reaction. Both their cyclic voltammograms show, as expected, two one-electron quasi- reversible redox ...Two tetrathiafulvalene-calix[4]arene assemblies (TTF-calix-1 and TFF-calix-2) have been synthesized by the click reaction. Both their cyclic voltammograms show, as expected, two one-electron quasi- reversible redox behavior. The UV-vis absorption spectra studies show that these two assemblies undergo progressive oxidation at the TFF moiety in presence of increasing amounts of Cu2+ or Hg2+. Moreover, the absorption studies show intermolecular electron transfer between compounds TrF-calix- I or TI'F-calix-2 and p-chloranil may be promoted by specific metal ions such as Pb2+, Sc3+ etc.展开更多
The interaction between amino acid drugs, aminobutyric acid, carbocisteine and levodopa, with chloranil was studied spectrophotometrically. The conditions were investigated and optimized. The interaction obeyed Beer'...The interaction between amino acid drugs, aminobutyric acid, carbocisteine and levodopa, with chloranil was studied spectrophotometrically. The conditions were investigated and optimized. The interaction obeyed Beer's law over the range of 0.2-8.7, 1.2-20 and 2-26.4 μg/mL for aminobutyric acid, carbocisteine and levodopa, respectively. The validity was compared with that by the official methods^1,3,5 and the recovery studies of standard addition method, the result is satisfactory. The proposed method has been successfully applied to the determination of the above drugs in tablets.展开更多
Chloranil through condensation reaction with vicinal diamine such as diaminomaleonitrile produced heterocyclic monomer, p-benzoquinonebis[2,3-b; 2',3'-b']pyrazine-5,6-dinitrile. The tetranitrile monomer was cyclo-t...Chloranil through condensation reaction with vicinal diamine such as diaminomaleonitrile produced heterocyclic monomer, p-benzoquinonebis[2,3-b; 2',3'-b']pyrazine-5,6-dinitrile. The tetranitrile monomer was cyclo-tetramerised using lithium/pentanol and acetic acid affording the corresponding tetrap-benzoquinone bis[2,3-b; 2',3'-b']pyrazinoporphyrazine)]- based network polymer (2H-Pz). The tetranitril monomer was cyclo-tetramerised using metal salt and quinoline affording the corresponding porphyrazinato-metal II-based network polymers (M-Pz), M = Co, Ni or Cu. Elemental analytical results, IR and NMR spectral data of the prepared molecules are consistent with their assigned formulations. Molecular masses and metal contents of the synthesized polymers proved to be of high molecular masses which confirm the efficiency of tetramerization polymerization and complexation reactions. The prepared pyrazinoporphyrazines were used as efficient catalysts for the oxidation of thiophenol and benzylthiol to their disulfides in the presence of air atmosphere. The results of oxidation of thiophenol and benzylthiol show that after 15 min the maximum yield of the corresponding disulfides reached 95%, 91%, respectively.展开更多
A spectrophotometric method for the determination of chlorhexidine acetate is described. The reaction between chlorhexidine acetate and chloranil took place in an alcohol-acetone solution at room temperature. The comp...A spectrophotometric method for the determination of chlorhexidine acetate is described. The reaction between chlorhexidine acetate and chloranil took place in an alcohol-acetone solution at room temperature. The composition of the charge transfer complex is 1:2. Beer's law is obeyed in the concentration range of 15–270 μg·mL?1 with correlation coefficient 0.9995. The apparent molar absorptivity is 2.21 × 103 L·mol?1·cm?1 at 412 nm. The method is accurate (with a recovery af 100 ± 1.6% ) and precise (RSD =1.0%). It was successfully applied to determine chlorhexidine acetate in suppository or disinfectant solution.展开更多
Photoinduoed reaction of chloranil (TCBQ) with 2-methylfuran la and 2,5-dimethylfuran 1b in benzene gave addition products 2a and 2b respecvely together with tetrachlorohydroquinone 3. A mechanism of sequential electr...Photoinduoed reaction of chloranil (TCBQ) with 2-methylfuran la and 2,5-dimethylfuran 1b in benzene gave addition products 2a and 2b respecvely together with tetrachlorohydroquinone 3. A mechanism of sequential electron and proton transfer from la or 1b to ~3TCBQ followed by coupling of the furfuryl and semiquinone radical pairs was proposed and is evidenced by the photo-CIDNP studies of the TCBQ-1a and TCBQ-1b systems.展开更多
The CIDNP observations indicated that photoreaction of methylfurans with chloranil resulted not only furylmethyl hydroxyphenyl ethers via radical pairs but induced furyl radical isomerization to the derivatives of cyc...The CIDNP observations indicated that photoreaction of methylfurans with chloranil resulted not only furylmethyl hydroxyphenyl ethers via radical pairs but induced furyl radical isomerization to the derivatives of cyclopropene,propadiene and pyran.展开更多
基金supported by the National Natural Science Foundation of China(Nos.21172105 and 20872058)
文摘Two tetrathiafulvalene-calix[4]arene assemblies (TTF-calix-1 and TFF-calix-2) have been synthesized by the click reaction. Both their cyclic voltammograms show, as expected, two one-electron quasi- reversible redox behavior. The UV-vis absorption spectra studies show that these two assemblies undergo progressive oxidation at the TFF moiety in presence of increasing amounts of Cu2+ or Hg2+. Moreover, the absorption studies show intermolecular electron transfer between compounds TrF-calix- I or TI'F-calix-2 and p-chloranil may be promoted by specific metal ions such as Pb2+, Sc3+ etc.
文摘The interaction between amino acid drugs, aminobutyric acid, carbocisteine and levodopa, with chloranil was studied spectrophotometrically. The conditions were investigated and optimized. The interaction obeyed Beer's law over the range of 0.2-8.7, 1.2-20 and 2-26.4 μg/mL for aminobutyric acid, carbocisteine and levodopa, respectively. The validity was compared with that by the official methods^1,3,5 and the recovery studies of standard addition method, the result is satisfactory. The proposed method has been successfully applied to the determination of the above drugs in tablets.
文摘Chloranil through condensation reaction with vicinal diamine such as diaminomaleonitrile produced heterocyclic monomer, p-benzoquinonebis[2,3-b; 2',3'-b']pyrazine-5,6-dinitrile. The tetranitrile monomer was cyclo-tetramerised using lithium/pentanol and acetic acid affording the corresponding tetrap-benzoquinone bis[2,3-b; 2',3'-b']pyrazinoporphyrazine)]- based network polymer (2H-Pz). The tetranitril monomer was cyclo-tetramerised using metal salt and quinoline affording the corresponding porphyrazinato-metal II-based network polymers (M-Pz), M = Co, Ni or Cu. Elemental analytical results, IR and NMR spectral data of the prepared molecules are consistent with their assigned formulations. Molecular masses and metal contents of the synthesized polymers proved to be of high molecular masses which confirm the efficiency of tetramerization polymerization and complexation reactions. The prepared pyrazinoporphyrazines were used as efficient catalysts for the oxidation of thiophenol and benzylthiol to their disulfides in the presence of air atmosphere. The results of oxidation of thiophenol and benzylthiol show that after 15 min the maximum yield of the corresponding disulfides reached 95%, 91%, respectively.
基金Project (No. 29392601) supposal by the National Natural Science Foundation of China
文摘A spectrophotometric method for the determination of chlorhexidine acetate is described. The reaction between chlorhexidine acetate and chloranil took place in an alcohol-acetone solution at room temperature. The composition of the charge transfer complex is 1:2. Beer's law is obeyed in the concentration range of 15–270 μg·mL?1 with correlation coefficient 0.9995. The apparent molar absorptivity is 2.21 × 103 L·mol?1·cm?1 at 412 nm. The method is accurate (with a recovery af 100 ± 1.6% ) and precise (RSD =1.0%). It was successfully applied to determine chlorhexidine acetate in suppository or disinfectant solution.
文摘Photoinduoed reaction of chloranil (TCBQ) with 2-methylfuran la and 2,5-dimethylfuran 1b in benzene gave addition products 2a and 2b respecvely together with tetrachlorohydroquinone 3. A mechanism of sequential electron and proton transfer from la or 1b to ~3TCBQ followed by coupling of the furfuryl and semiquinone radical pairs was proposed and is evidenced by the photo-CIDNP studies of the TCBQ-1a and TCBQ-1b systems.
文摘The CIDNP observations indicated that photoreaction of methylfurans with chloranil resulted not only furylmethyl hydroxyphenyl ethers via radical pairs but induced furyl radical isomerization to the derivatives of cyclopropene,propadiene and pyran.