Enhanced enantioselective recognition with diastereoisomeric BINOL based chiral fluorescent boronic acid sensors.

We prepared the diastereoisomers of BINOL based bisboronic acid chiral probes (the probes are with dual chirogenic centers) for enantioselective recognition of chiral analytes, such as tartaric acids, D-sorbitol, etc. We found the diastereoisomeric probes give different emission intensity-pH profiles, a phenomenon was reported, probably, for the first time. We found that with the second chirogenic center, the selectivity of the probes toward chiral analytes can be improved. For example, the diastereoisomeric probes give drastically different response to D-sorbitol, the same selectivity was not found for the BINOL bisboronic acid probes with single chirogenic center. Our result with the diastereoisomeric probes is helpful for design of new chiral molecular probes to enhance the selectivity of the boronic acid sensors toward chiral analytes.