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A series of 2-aminothiazoles is prepared in moderate-to-good yields by the direct coupling of ketones and thiourea using I2/dimethyl sulfoxide as a catalytic oxidative system. This method avoids the preparation of lachrymatory and toxic α-haloketones and the use of an acid-binding agent, thus providing a more convenient approach to 2-aminothiazoles compared to the Hantzsch reaction.

A novel and simple fluorescence probe was synthesized from benzo [1,2-b:4,5-b']dithiophene (BDT) and trimethylsilylethyne via Sonogashira reaction, and showed highly selective and sensitive fluorescence decreasing response towards F  . The probe molecule turned to a weakly fluorescent terminal alkyne moiety because its trimethylsilyl (TMS) group was cleaved by fluoride, which was proved by 1 H NMR titration. Whereas no distinct fluorescent changes were observed with the addition of other anions, such as Cl  , Br  , I  , AcO  and 2 4 H PO -. Upon the addition of F  , the maximum fluorescence emission wavelength shifted from 460 nm to 450 nm with a decrease of fluorescence intensity by 40% within 20 s. Moreover, the detection limit towards F  was calculated to be as low as 73.5 nmol/L.