New and efficient high Stokes shift fluorescent compounds: unsymmetrically substituted 1,2-bis-(5-phenyloxazol-2-yl)benzenes via microwave-assisted nucleophilic substitution of fluorine

摘要

Two new unsymmetric derivatives of 1,2-bis-(5-phenyloxazol-2-yl)benzene (ortho-POPOP) were synthesized via microwave-assisted nucleophilic substitution of fluorine which appears to be significantly more efficient compared with conventional thermal activation. The compounds synthesized are characterized by high fluorescence Stokes shifts (6000-11,000 cm~(-1)) in solvents of various polarity, intermediate-to-high fluorescence quantum yields and lifetimes in the range of several nanoseconds.