BisBINOL-Based Fluorescent Probes: Effect of Alkane Linkers and Chemo- and Enantioselective Recognition of Arginine

A series of bisBINOL-based fluorescent probes, which contain two BINOL units linked by an alkane chain of varying length, were synthesized and characterized. It was found that the chain length of the alkane linker has strong effect on the fluorescence response of these compounds toward amino acids. Among them, compound (<i>S</i>,<i>S</i>)-<b>6</b> that contains a six-carbon alkyl chain linker exhibits highly chemoselective and enantioselective fluorescence enhancement with arginine in the presence of Zn²⁺, but other compounds show much less selective fluorescence response. Spectroscopic studies have been conducted to investigate the mechanism of this process.