In Situ Generated 1:1 Zn(II)-Containing Polymer Complex Sensor for Highly Enantioselective Recognition of N-Boc-Protected Alanine

A novel chiral (S)-BINAM-based fluorescence polymer sensor was designed and synthesized by the polymerization of 5,5'4(2,5-dioctyloxy-1,4-phenylene)bis-(ethyne-2,1-diyl)bis(2-hydroxy-3-(piperidin-1-ylmethyl)-benzaldehyde (M-1) with (S)-2,2'-binaphthyldiamine (S-BINAM, M-2) via Schiff's base formation. The resulting chiral polymer sensor shows very weak fluorescence but exhibits the obvious fluorescence enhancement response toward Zn2+. The in situ generated 1:1 Zn(II)-containing complex of chiral polymer can serve as a fluorescence sensor for highly enantioselective recognition of N-Boc-protected alanine, and the value of enantiomeric fluorescence difference ratio (ef) can reach as high as 6.90. This is the first report on the in situ generated chiral polymer complex used as a fluorescence sensor for highly enantioselective recognition of N-Boc-protected alanine.