Recognition of Anion by Dual Fluorescent Sensor Based on the Intramolecular Charge Transfer in p-Dimethylaminobenzoylhydrazine
In t ramo lecu lar charge t ran sfer ( ICT ) dual f luo rescence of p 2dim ethylam ino2 benzoylhydrazine (DMABH ) in aceton it rile w as found to show a h igh ly select ive respon se to HSO -4 over several other an ions. The inten sity rat io of the CT to L E em ission and the to tal f luo rescence intensity of DMABH decreased with increasing bisulfate concent ration. While the dual f luo rescence respon se w as very sim ilar to that of DMABA at a low HSO4 concen t rat ion, the CT in ten sity decreased drast ically and the L E in ten sity rem ained almo st con stan t, how ever, the difference w as ob served at a h igh HSO -4 concen t rat ion, in w h ich bo th the CT and L E in ten sit ies of DMABH decreased. A different recogn it ion m echan ism f rom that of DMABA w as suggested fo r DMABH in w h ich hydrogen bonding and p ro ton izat ion w ere the recogn it ion in teract ion s at low and high HSO4 concen t rations,respectively.