Synthesis Of Sulphamidyl Azobenzene Derivatives And Crystal Violet Lactone Complexes And Studies On Its Thermochromic Properties

The main work of this thesis includes the following three parts: The first part: The development of the reversible thermochromic compounds was viewed based on the references and materials about this topics. Much attention was paid to the basic classifications, the mechanism and the application of reversible thermochromic schiff bases and triphenylmethane phthalide compounds. Based on many references we choose to synthesize the compounds as 4-sulphamidyl azobenzene derivatives and 4 ' -sulphamidylbenzylazo-4-hydroxy-3-anils derivatives and 3, 3-bis-[(p-dimethylamino)phenyl]-6-dimethyl amino phthalide.The second part: The intermediates of sulfanilamide and 5-(4' -sulphamidylbenzylazo)salicylaldehyde were prepared in advance, respectively. Series I , including seventeen compounds in which fifteen compounds were novel without report in reference, were synthesized by means of nucleophilic addition reaction with substituted aromatic amine. Then the intermediates of m-dimethylaminobenzoic acid and3, 3-bis-[(p-dimethylamino)phenyl]-(p-dimethylamino-m-formyl)benzyl methane were prepared respectively, CVL was synthesized by means of oxidation ring-closed reaction with ammonium persulfate. And series II, including forty-eight compounds in which forty-five compounds were novel, were synthesized by means of chelation reaction between phenols, aromatic amines, carboxylic acids , Lewis acids and 3,3-bis-[(p-dimethylaraino)phenyl]-6-dimethyl amino phthalide.Further research was performed on the conditions of the synthesis of the intermediate m-dimethylaminobenzoic acid.The third part: We observed the thermochromic phenomena of all compounds directly by eyes after heated. DTA and DSC testing were performed on some exemplifiar compounds which have the properties of irreversible or reversible thermochromism, respectively. Based on plenty of experimental data obtained from the testing, we expound on the thermochromic properties of objective compounds, and find out the relationship between the structure of these compounds and its thermochromic properties, and further research on the thermochromic mechanism of these compounds were performed systematically. The value of Ea was calculated through the formula of thermo-kinetic theory. And the corresponding classification of these reversible thermochromic compounds were also performed at the same time.