| 摘要: | 本研究即合成一系列2-胺基-1,3,4-噻二唑類化合物，產率為32~94%，合成條件為胺基硫尿： (1)與芳香族(或雜環)甲酸於三氯氧化磷中加熱迴流可得7種(Ⅰa~Ⅰe、Ⅱa~Ⅱb) (2)與異尼古丁酸反應時使用聚磷酸為脫水縮合劑環化為2-胺基-5-(4-吡啶基)-1,3,4-噻二唑(Ⅰf) (3)與甲酸反應則使用濃鹽酸即可得2-胺基-1,3,4-噻二唑(Ⅰg) (4)與苯甲醛先縮合為1-苯基硫卡半腙(Ⅲ)經氯化鐵之氧化與環化成2-胺基-5-苯基-1,3,4-噻二唑(Ⅰa) 並且以此類化合物為原料與R酸、2-萘酚及N,N-二甲基苯胺合成一些偶氮(N=N)染料，與4-二甲胺基苯甲醛合成吖次甲基(C=N)染料。將所合成之1,3,4-噻二唑系染料與苯系染料比較，觀察其可見光譜之最大吸收波長差異，所得結果顯示1,3,4-噻二唑環確實有達到紅位移效果。在R酸偶氮染料中，1,3,4-噻二唑系染料相較苯系染料於鹼性水溶液中UVλmax紅位移了9~59nm，在2-萘酚偶氮染料中，乙醇溶液加鹼條件下為53~75nm，N,N-二甲基苯胺偶氮染料中，乙醇溶液中則為86~107nm。而在吖次甲基染料中，亦再度顯示雜環具此項特性，波長差距66nm。合成之1,3,4-噻二唑吖次甲基染料意外觀察到Ⅸa與Ⅸd固體具有強螢光性質，溶於DMF中測得最大螢光放射波長分別為524、540nm。 A series of 2-Amino-1,3,4-thiodazole has been synthesized which exhibit various yields of 32~94%. The reaction conditions were that thio- semicarbazide: (1) and aromatic(or heterocyclic)acid were put into Phosphorus oxy- chloride (POCl3), then were heated and refluxed, seven kinds of Ⅰa ~ Ⅰe, Ⅱa~Ⅱb can be obtained. (2) reacted with isonicotinic acid and cyclodehydration by Poly- phosphoric acid (PPA). 2-amino-5-(4-pyridyl)-1,3,4-thiadiazole(Ⅰf) was obtained. (3) reacted with formic acid in concentrated hydrochloride, 2-amino- 1,3,4-thiadiazole(Ⅰg) can be obtained. (4) and benzaldehyde were underwent condensation reaction to 1-phenyl- thiosemicarbazone(Ⅲ). Then it was oxidized and cyclized by ferric chloride to 2-amino-5-phenyl-1,3,4-thiadiazole(Ⅰa) These 1,3,4-thiadiazole derivatives were taken as raw materials. then they were coupled with R-acid,2-naphthol and N,N-dimethylaniline to synthesized some azo (N=N) dyes; condensed with 4-dimethylamino- benzaldehyde to get azamethine(C=N) dyes. Compared and observed the difference between 1,3,4-thiadiazole’s dyestuffs and benzene’s dyestuffs there maximum of the absorptive wavelengths of the visible light, the result revealed that bathochromic shift effect was occurred when 1,3,4-thiadiazole ring existence. In R-acid azo dyes , the UVλmax was bathochromic shifted 9~59 nm in 1,3,4-thiadiazole dyes than in azobenzene dyes under basic solution. Under basic ethanol solution, the difference of UVλmax is 53~75 nm in 2-naphthol azo dyes; Under ethanol solution, 86~107nm in N,N-dimethylaniline azo dyes. It exhibited similar characteristic again in azamethine dyestuff. And the difference of UVλmax is 66nm. Unexpectedly, strong fluorescence can be observed in Ⅸa and Ⅸd of 1,3,4-thiadiazole azamethine dyes. The maximum emission Fluore- Scence of wavelength is 524 and 540nm, respectively. |
