Synthesis And Application Of Novel BODIPY/aza-BODIPY Fluorescent Dyes

Fluorescent dyes,although the type and structure has been studied for a long time,but there are still shortcomings.This paper is devoted to the study of a new type of BODIPY/aza-BODIPY dye which has not been reported yet,looking for its potential applicability.A series of new BODIPYs/aza-BODIPYs with a methylthio group were Herein prepared.Introduction of the electron-donating methylthio substituent into such dyes could reduce the fluoresecence quantum yield,red-shift its emission spectra,provide higher extinction coefficients and larger Stokes' shift.Oxidation of the thioether of BODIPY dye 4 into the corresponding electron-withdrawing sulfoxide by HClO can restore the quantum yield and blue-shift its emission spectra,and dye 4 was highly sensitive and selective to HClO.Five-membered-ring-fused BODIPYs and aza-BODIPYs were herein prepared.Such BODIPY/aza-BODIPY dyes with a five-membered ring have long wavelength absorptions/emissions,high extinction coefficients,peak fluorescence and narrow excitations/emissions.But,the planar structure of five-membered-ring fused BODIPY did not promote the photophysical properties over these of six-membered-ring fused BODIPY,except the molar extinction coefficient within the range of allowable error.MO calculations well supported and explained the near absorption maxima between BODIPY bearing a five-membered ring and BODIPY bearing a six-membered ring.