Fluorescencijski kemijski senzori temeljeni na kumarinu

Kumarini su se zadnjih godina pokazali kao obećavajuće strukture u dizajnu i sintezi novih kemosenzorskih molekula zbog svojih fluorescentnih svojstava, a otkrićem click-kemije predstavljen je novi način sinteze spojeva jednostavnim i brzim postupcima. Ovim načinom sinteze dizajnirani su mnogobrojni kemosenzori, a u radu je dan pregled dosad istraženih kemijskih senzora za metalne ione i pH temeljenih na derivatima kumarina i triazola. Cilj rada bila je sinteza i spektroskopska karakterizacija novog derivata kumarina kao potencijalnog kemijskog senzora. Ciljani spoj 7-(4-(4-(dimetilaminofenil)-1H-1,2,3-triazol-1-il)-4-metil-2H-kromen-2-on 3 pripravljen je klasičnom reakcijom organske sinteze i click-reakcijom odgovarajućeg azido derivata kumarina i 4-etinil-N,N-dimetilanilina uz Cu(I) kao katalizator. Kako bi se ispitala mogućnost primjene spoja kao optičkog pH senzora i senzora za metalne ione, ispitana je promjena njegovih spektroskopskih svojstava ovisno o pH otopine i u prisutnosti različitih metalnih soli primjenom UV/Vis i fluorimetrijske spektroskopije. Spoj 3 pokazuje ovisnost spektrofotometrijskih svojstava o vrijednosti pH otopine, te je zbog toga potencijalni pH senzor. Preliminarna ispitivanja u otopinama etanola s dodatkom različitih metalnih soli pokazala su značajan utjecaj prisutnosti Hg2+ i Li+ iona na apsorpcijski i emisijski spektar spoja 3. Potrebno je provesti dodatna detaljnija ispitivanja kako bi se sa sigurnošću utvrdila senzorska primjena spoja 3 za navedene metale. Coumarins are promising structures in the synthesis and design of novel chemosensors as they exibit fluorescence properties. With the discovery of click-chemistry, a new way of synthesizing compounds with simple and quick synthetic steps has been found. A significant number of potential chemosensors was designed by the click chemistry approach. In this work, an overview of chemosensors for metal ions and pH based on the derivatives of coumarin and triazole is given. This work presents the synthesis and spectroscopic characterization of a novel coumarin derivative as potential chemosensor. Targeted compound 7-(4-(4-(dimethylamino)phenyl)-1H-1,2,3-triazol-1-yl)-4-methyl-2H-chromen-2-one 3 was prepared by classical chemical reaction of organic chemistry and by click-reaction from the corresponding azido-coumarin derivative and 4-ethynyl-N,N-dimethylaniline in the presence of Cu(I) as catalyst. In order to determine the possibility of application as pH and metal ion sensor, the changes of the compounds spectroscopic properties depending on the pH value and in presence of different metal ions were studied by UV/Vis and fluorescence spectroscopy. Coumpound 3 shows dependance of spectroscopic properties on the pH value of the solution, and is therefore a potencial pH sensor. Preliminary testing in ethanol solutions with the addition of various metal salts showed a significant influence in the presence of Hg2+ and Li+ ions in absorption and emission spectrum of compound 3. It is required to carry out more detailed testing to determine the sensing application of compound 3 for said metals.