title: Rational design of a fluorescent sensor to simultaneously determine both the enantiomeric composition and the concentration of chiral functional amines.
abstract: A fluorescent molecular probe, a 1,1'-bi-2-naphthol (BINOL)-based bis(naphthylimine) compound (R)-4, is designed to exhibit very different fluorescent responses at two emission wavelengths toward a variety of chiral functional amines including diamines, amino alcohols, and amino acids. At one emission wavelength (λ1), it shows high sensitivity toward the substrates, and at another wavelength (λ2), it shows high enantioselectivity. This is the first rational design of such a dual responsive fluorescent sensor which can be used to simultaneously determine both the concentration and the enantiomeric composition of functional chiral amines by one fluorescent measurement. This strategy is potentially generally applicable for the construction of sensors for rapid assay of structurally diverse chiral substrates. When (R)-4 is treated with various chiral functional amines in the presence of Zn(OAc)2, its 2-naphthylamine units are displaced off to show large fluorescent enhancement at λ1 = 427 nm (I1) due to the restored emission of 2-naphthylamine. The combination of the remaining chiral binaphthyl unit with the chiral substrates leads to highly enantioselective fluorescent enhancement at λ2 > 500 nm (I2). Since I1 is only concentration dependent but independent of the chiral configuration, it allows the determination of the substrate concentration. The highly enantioselective I2 allows the determination of the enantiomeric composition. Thus, using one fluorescent probe with one fluorescent measurement, both the concentration and the enantiomeric composition are determined. The dual responsive mechanism of (R)-4 is studied by using various spectroscopic methods including fluorescence, UV-vis, NMR, and mass analyses.
authors: †Key Laboratory of Green Chemistry and Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu, China 610064.
authors: Kaili
authors: K
authors: Wen
authors: †Key Laboratory of Green Chemistry and Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu, China 610064.
authors: Shanshan
authors: S
authors: Yu
authors: †Key Laboratory of Green Chemistry and Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu, China 610064.
authors: Zeng
authors: Z
authors: Huang
authors: †Key Laboratory of Green Chemistry and Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu, China 610064.
authors: Liming
authors: L
authors: Chen
authors: †Key Laboratory of Green Chemistry and Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu, China 610064.
authors: Meng
authors: M
authors: Xiao
authors: †Key Laboratory of Green Chemistry and Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu, China 610064.
authors: Xiaoqi
authors: X
authors: Yu
authors: †Key Laboratory of Green Chemistry and Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu, China 610064.|‡Department of Chemistry, University of Virginia, Charlottesville, Virginia 22904-4319, United States.
authors: Lin
authors: L
authors: Pu