Visible Light Excitable SCN − Selective Fluorescence Probe Derived from Thiophene

An efficient fluorescence probe, 4‐methyl‐2,6‐bis((thiophen‐2‐ylmethylimino)methyl)phenol (DFPTMA) and its SCN − adduct has been synthesized and characterized by different spectroscopic techniques like 1 H NMR, 13 C NMR, QTOF‐MS ES + , UV‐Vis and FTIR spectroscopy. Single crystal X‐ray structure of DFPTMA is reported. In presence of SCN − , DFPTMA exhibits significant fluorescence enhancement ( λ Ex , 455 nm, λ Em , 504 nm) in aqueous methanol (water‐methanol, 1:4, V / V , 0.1 mol/L HEPES buffer, pH 7.4). Common bio‐relevant anions viz . CH 3 COO − , NO 2 − , NO 3 − , Cl − , Br − , I − , SO 4 2− , HSO 4 − , N 3 − , HAsO 4 2− , Cr 2 O 7 2− , H 2 PO 4 − , ClO 4 − , NCO − , CN − , CO 3 2− , F − , PO 4 3− , S 2− , HS − do not interfere in the recognition of SCN − . Lowest detection limit for SCN − is 0.88 µmol/L with response time <5 min. The SCN − assisted enhancement in emission intensity may be attributed to the formation of H‐bond which enhances the rigidity of the molecular assembly.