This outlook describes two strategies to simultaneously determine the enantiomeric composition and concentration of a chiral substrate by a single fluorescent measurement. One strategy utilizes a pseudoenantiomeric sensor pair that is composed of a 1,1′-bi-2-naphthol-based amino alcohol and a partially hydrogenated 1,1′-bi-2-naphthol-based amino alcohol. These two molecules have the opposite chiral configuration with fluorescent enhancement at two different emitting wavelengths when treated with the enantiomers of mandelic acid. Using the sum and difference of the fluorescent intensity at the two wavelengths allows simultaneous determination of both concentration and enantiomeric composition of the chiral acid. The other strategy employs a 1,1′-bi-2-naphthol-based trifluoromethyl ketone that exhibits fluorescent enhancement at two emission wavelengths upon interaction with a chiral diamine. One emission responds mostly to the concentration of the chiral diamine and the ratio of the two emissions depends on the chiral configuration of the enantiomer but independent of the concentration, allowing both the concentration and enantiomeric composition of the chiral diamine to be simultaneously determined. These strategies would significantly simplify the practical application of the enantioselective fluorescent sensors in high-throughput chiral assay. 1. Introduction The study of enantiomerically pure chiral compounds has found increasing importance in many areas, such as pharmaceutical industry [1, 2], agrochemical area [3], and food analysis [4, 5]. For example, the stereochemistry of drugs can significantly affect their biological activity due to the inherently chiral environment of the biological systems. The US FDA issued a policy statement in 1992 and strongly encouraged the development of single isomers [6]. Therefore, easily and economically performed methods for acquiring enantiopure compounds have attracted enormous research interest. The development of asymmetric catalysis has provided the pathway to preferentially generate one enantiomer over the other from a reaction by using a chiral catalyst. This not only can avoid the labor-intensive and time-consuming separation of enantiomers, but also can eliminate the waste of the undesired enantiomer [7, 8]. The key to develop an efficient asymmetric catalysis reaction is to identify a catalyst structure as well as its most suitable reaction conditions including factors such as solvent, temperature, additive, reaction time, and stoichiometry. Therefore, this screening process can be extremely
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