A Study On The Fine Chemicals By Electrospray Ionization Mass Spectrometry

Ionization of ESMS (Electrospray Ionization Mass Spectrometry), taking place directly in constringent phase and forming gas phase ions under mild conditions, is important to apply as "soft" ionization technique in analysis of fine chemicals. The technique can not only provides exact molecular weight, but also can be used to test complex with uncovalent bond or unstable active species, therefore, becomes an important method to character structure of compounds and study reaction mechanism. In this thesis, the identification of reactive dyes and the reaction mechanism of organic synthesis, as well as the stability of the complexes were investigated by HPLC-MS, in-source CID (Collision Induced Dissociation), and MS/MS spectrometry techniques is presented.The dissertation outlined the rules of MS characteristics for the active groups in the dyes by a systematic analysis of different types of reactive dyes using ESMS. Over 100 reactive dyes of different structures were examined from the results of ESMS via characteristic fragment species and the differential molecular weight of the derivatives formed in the reaction between reactive groups and organic amines. These methods are speedy, accurate and reliable, and would greatly simplify the conventional analysis process for reactive dye structures.The intermediate products in reductive-alkyl-reduction of m-, or p-(β-hydroxy ethyl sulfonyl)anilines with acetaldehyde were examined by HPLC/MS tracing method. The presence of the derivatives from partial hydrogenation of the corresponding Schiff's bases and further the additional products from acetaldehyde and secondary amines found would readily confirm the course of the hydrogenation of Schiff's bases and provide a controlling method for optimizing the reaction conditions.The study of Pschorr cyclization of 1,8-naphthalic anhydride diazonium salts in which oxygen or sulfur atom be as a bridge atom was carried out using HPLC/MS, a method for identifying the isomers established and the ratio between isomers determined, demonstrating the phenomena of the existence of aromatic radical-induced inner aromatic 1,5-hydrogen transfer reactions.The coordination nature of 4-(N,N-dimethylamino)pyridine (DMAP) with Salen-or Salan-(where the tetradentate N,N'-disubstituted bisaminophenoxide is designated as Salan, a saturated version of the Schiff-base Salen ligand) chromium complexes was studied by electrospray ionization mass spectrometry (ESI-MS), and the stability of the mono-coordinate ions were studied by ESI-MS/MS. It was approved that mono-DMAP ion coordinating with SalenCr(III)X or SalanCr(III)X are active species in the chain increase of copolymerization of CO2 and propylene oxide by monitoring the reaction. It was found that both the catalytic activity and inducement time were apparently different in both systems, thus it provide a controlling method for improving the catalytic activities in such bi-combination systems.The effect of different groups on photosensitized dyes was investigated by using in-source CID and MS/MS techniques by comparison with the differences between two CID spectra, indicating that with the increase of ability of donating electrons on pyridine ring would enhance the stability of both the ligands and dyes, thus would provide a controlling method for the study of stability of photosensitized dyes.