The Synthesis And Performance Research Of Cyanide Ion Chemosensor Molecule Based Chemical Reaction

This thesis is divided into three chapters:Chapter 1: The review of cyanide ion sensor Summarized related literature reports of cyanide ion sensors in recent years, expounded the research status and progress. We introduce the design and application based on the different response mechanisms such characteristics of cyanide ion sensor: 1.2 Probes based on small organic molecule; 1.3 Probes based on metal complexes; 1.4 Probes based on polymeric frameworks; 1.5 Probes based on nanoparticles. Meanwhile, on the basis of literature review, we put forward the research approach of this thesis.Chapter 2: The synthesis and performance research of cyanide ion chemosensor based on dicyano-vinyl group as the reaction sites This sensor was synthesized via a simple, efficient and environmentally friendly route in pure water without using any catalyst. The design focuses on utilizing the dicyano-vinyl group as the identification of reaction sites. We introduced an electron-donating group, such as dimethylaminia, to construct an acceptor–donor–acceptor(A-D-A) molecule which could change the initial charge distribution of the chemosensor and improves intramolecular charge transfer(ICT). This technique can impact the fluorescent properties effectively. The electron-withdrawing nature of dicyano-vinyl group can be modulated by CN-, which i nterrupts π-conjugation to change the spectrum, resulting in very high sensitivity and selectivity to CN-. To further confirm the effect of intramolecular charger transfer on recognition, molecular CS2 without an electron donating group was synthesized to compared with CS1.Chapter 3: The synthesis optimization of cyanide ion chemosensor molecules CS1 Because the cyanide ion sensor CS1 adopted in the design of the synthetic form of carbon carbon double bond as a recognition site for reaction, so the molecules synthesis process and the corresponding technology in the previous chapter CS1 sensor was studied, respectively from different reaction system, different reaction time,reaction temperature and catalyst obtained under the condition of different yields to evaluate and select what we consider the optimal reaction conditions.Chapter 4: The synthesis and performance research of cyanide ion chemosensor based on Schiff-base as the reaction sites The sensor is based on Schiff-base(-C=N-) as recognition sites, naphthalene as fluorescent signal groups, through addition reaction with CN- then induced the hydrolysis of schiff’s-base to realize and recognized the cyanide. This process has good selectivity for identifying the cyanide(the anion with alkalinity(F-, Ac O-, H2PO4-) without disturbing the process of identification), High sensitivity(detection limit reached 10-8 magnitude), Short reaction time(response time is less than 1 minute), Dual channel color fluorescence of CN- recognition, etc. Therefore the sensor molecule has potential application value.