Synthesis and optical characterization of novel heteroaromatic chromophores

Cilj ovog rada je sinteza i optička karakterizacija novih derivata benzimidazola koji u svojoj strukturi sadrže 1,2,3-triazolni prsten u svrhu određivanja njihove senzorske aktivnosti. Novi spojevi 2-[(4-nitro)benz-2-iliden)amino]benzimidazol (spoj 3), 2-[(4-amino)benz-2-iliden)amino]benzimidazol (spoj 5), 2-[(4-azido)benz-2-ilidene)amino]benzimidazole (spoj 6) i 2-{4-[(4-fenil)-1,2,3-triazol-1-il]benzilidenamino}benzimidazol (spoj 8) uspješno su sintetizirani reakcijama klasične i „click“ kemije, dok spoj 2-{4-[4-(4-aminofenil)-1,2,3-triazol-1-il]benzilidenamino}benzimidazol 7 nije uspješno izoliran zbog preniske koncentracije i prevelikog broja nusprodukata. Strukture spojeva 3, 5 i 8 potvrđene 1H-NMR spektroskopijom. Detaljna karakterizacija fotofizičkih i kiselo-baznih svojstava u svrhu ispitivanja potencijalne primjene u optičkim kemijskim senzorima je provedena za spoj 3 i 8. Spoj 3 je okarakteriziran UV-vidljivom i fluorescencijskom spektrofotometrijom u otapalima različite polarnosti, univerzalnim puferima u rasponu vrijednosti pH od 1 do 13 te u prisustvu različitih metalnih iona. Također su provedena spektrofotometrijska ispitivanja spoja 8 u univerzalnim puferima pri graničnim vrijednostima pH te u prisustvu Zn2+, Ag+ i Al3+ iona. Spoj 3 ima potencijalno djelovanje kao pH senzor, ali nije pokazao poželjna svojstva za uporabu u senzorima za metale. Spoj 8 je potrebno dodatno ispitati kako bi se definitivno zaključila njegova senzorska aktivnost.The aim of this thesis was synthesis and optical characterization of novel benzimidazole derivates which incorporate 1,2,3-triazole ring in their structure, to prove their sensoring activity. Compounds 2-[(4-nitro)benz-2-ilidene)amino]benzimidazole (compund 3), 2-[(4-amino)benz-2-ilidene)amino]benzimidazole (compund 5), 2-[(4-azido)benz-2-ilidene)amino]benzimidazole (compund 6) and 2-{4-[(4-phenyl)-1,2,3-triazole-1-il]benzilidenamino}benzimidazole (compound 8) were succesfully synthesized using a combination of classical organic chemistry synthesis and „click“ chemistry reaction, while compund 2-{4-[4-(4-aminofenil)-1,2,3-triazole-1-il]benzilidenamino}benzimidazole (compund 7) was not succesfully isolated due to low concentration and significant amount of impurities. Structures of compunds 3, 4, 5 and 8 were determined by 1H-NMR spectroscopy. Compound 3 was characterized with UV-visible and fluorescence spectrophotometry in solvents of different polarity, universal buffers in pH range 1 to 13 and in the presence of different metal ions. Compound 8 was spectrophotometricaly characterized in marginal values of pH, and in the presence of Zn2+, Ag+ i Al3+ ions. Compund 3 shows potential activity as a pH sensor in some solvents (water, acetone and acetonitrile), but it did not prove itself a good sensor for detecting metal ions. For compound 8, additional experiments are needed to be sure about its sensor activity