Synthesis Of Pyridylazo Amines Reagents And Its Application To The Spectral Analysis And Laser Thermal Lens Analysis

Pyridylazo reagents because of its good sensitivity,high selectivity, and was appliedin many fields. In order to get the better of chromogenic reagent,we read a lot ofliterature and reference books,know reagent structure on its performance has a greatinfluence, So we in the pyridine ring4is introduced into the synthesis of methyl,tworeported from pyridylazo reagents:2-（5-nitro-4-methyl-2-pyridylazo）-5-dimethylamino-aniline（5-NO₂-4-CH₃-PADMA）and2-（5-bromide-4-methyl-2-pyridylazo）-5-dimethylaminoaniline（5-Br-4-CH₃-PADMA）,at the same time also synthesized5-（5-iodine-2-pyridyla-zo）-2,4-diaminotoluene（5-I-PADAT）and2-（5-bromide-2-pyridylazo）-5-dimethylaminoaniline（5-Br-PADMA）and the study of its application.This thesis includes two aspects: first, review; second, research report.First, review: a brief introduction of the development of pyridylazo reagents and itsapplication in analytical chemistry.Second, research reports: first of all, two new reagents,5-NO₂-4-CH₃-PADMAand5-Br-4-CH₃-PADMA,and the structures and compositions are characterized byinfrared spectroscopy（IR）, elemental analysis and nuclear magnetic resonancespectroscopy （1HNMR）.Secondly, studied by5-NO₂-4-CH₃-PADMA,5-Br-4-CH₃-PADMA,5-I-PADAT,5-Br-PADMA four kinds of reagents and noble metal ions chromogenic reaction,asfollows:1. By dual-wavelength overlapping Spectrophotometry Determination of palladiumDetermination of palladium by Dual-wavelength Overlapping Spectrophotometry.In0.6².4mol·L-1perchloric acid solution, reagents with palladium to form blue-purplecomplex with molar ratio of1:1. The complex has two absorption peaks,respectively, in584nm and546nm.The molar absorptivity of5-I-PADAT-Pd（II） is1.18×105L·mol-1·cm-1at584nm and546nm plus. Beer’s law are obeyed in range of0¹.2μg·mL-1for palladium.The method used for molecular sieve and determination of trace amount ofpalladium, obtained satisfactory results.2.5-NO₂-4-CH₃-PADMA determination of palladiumSpectrophotometric determination of trace palladium is proposed the new method.In0.6².4mol·L-1sulfuric acid solution, reagents with palladium to form green-bluecomplex, The molar absorptivity of5-NO₂-4-CH₃-PADMA-Pd（II） is6.05×104L·mol-1·cm-1at621nm. Beer’s law are obeyed in range of0.0³.2μg·mL-1for palladium.The method used for molecular sieve,catalyst and determination of palladium, obtainedsatisfactory results.3.5-NO₂-4-CH₃-PADMA chromogenic reaction with cobalt and its applicationEstablishment of spectrophotometric determination of cobalt with the new method.InpH4.0⁷.0HAc-NaAc in the buffer solution, reagents with cobalt to form green-bluecomplex, The molar absorptivity of5-NO₂-4-CH₃-PADMA-Co（II） is6.02×104L·mol-1·cm-1at620nm. Beer’s law are obeyed in range of0.0¹.0μg·mL-1forcobalt.The method for the determination of cobalt in vitamin B12, obtained satisfactoryresults.4.5-Br-4-CH₃-PADMA determination of rhodiumSpectrophotometric determination of rhodium is proposed the new method. InpH4.2⁵.0HAc-NaAc in the buffer solution, reagents with rhodium to form green-bluecomplex, The molar absorptivity of5-Br-4-CH₃-PADMA-Rh（III） is1.57×105L·mol-1·cm-1at605nm. Beer’s law are obeyed in range of0¹.0μg·mL-1for rhodium.The method used for catalyst and determination of rhodium, obtained satisfactory results.5.5-NO₂-4-CH₃-PADMA laser thermal lens spectrometry determination of palladiumPresent laser thermal lens spectrometry determination of palladium new method. Inacidic solution, reagents with rhodium to form green-blue complex, The maximumabsorption wavelength of5-NO₂-4-CH₃-PADMA-Pd（II） is623nm. Linear range ofPd（II） is0.015～0.25mg·L-1respectively. The method used for geological samples anddetermination of trace palladium, obtained satisfactory results.6.5-NO₂-4-CH₃-PADMA laser thermal lens spectrometry determination of cobaltPresent laser thermal lens spectrometry determination of cobalt new method. Inacidic solution, reagents with cobalt to form green-blue complex, The maximumabsorption wavelength of5-NO₂-4-CH₃-PADMA-Co（II） is622nm. Linear range of Co（II） is0.015～0.1mg·L-1respectively. The method used for geological samples anddetermination of metallic cobalt, obtained satisfactory results.7.Cloud point extraction technique and laser thermal lens spectrometry fordetermination of palladiumCloud point extraction and laser thermal lens spectrometry determination ofpalladium. It is based on CPE of palladium （Ⅱ） ions as5-Br-PADMA complexes usingoctylphenoxypolyeth-oxyethanol （Triton X-114） as surfactant. The cloud point extractionparameters were optimized,and the study of laser thermal lens spectrometrymeasurement conditions.In pH3.0⁷.0range, reagents with palladium to form ahydrophobic complexes,20min equilibrated at60℃,3500speed centrifugal5min,phaseseparation, palladium can be quantitatively extracted into the surfactant Triton X-114micellar phase. After cloud point extraction,dissolved in ethanol surfactant phase,and addright amount of perchloric acid acidification,then by laser thermal lens spectrometrydetermination. Linear range of Pd（II） is0.004⁰.08μg·mL-1respectively. The method forthe determination of palladium in water samples, with satisfactory results.