| Chiral recognition has attracted much attention for it played a major role in separation of chiral drugs, asymmetric synthesis, the theory of stereochemistry and the chirality origin of life etc. However, it is still a challenge to realize a fast and convenient chiral recognition. Recently, aggregation-induced emission compounds have been shown to be highly selective and stable fluorescence sensors for biological and chemical analytes. Work related to chiral recognition based on AIE effects has not been reported. In this paper, the aggregation-induced emission compounds were applied to chiral recognition and enantiomer composition analysis. The following expected results were obtained.1. a-aromatic cinnamylnitrile derivatives8was synthesized and shown to be AIE compounds. It exhibited not only an exceptionally high enantioselectivity but was also applicable to a wide range of chiral carboxylic acids,18different chiral carboxylic acids could be enantioselectively recognized and the fluorescence intensity ratio of two enantiomers ranged from10to1.6x104. And the enantiomer composition of the chiral carboxylic acids could be quantitatively measured through using the compound8.2. It was found that simple AIE compounds could emit different intensity of fluorescence in gel, suspension and precipitates. The order of the intensity of the lighting as follow:opaque gel≈recipitates>suspensions>transparent gel>solution. So that the AIE compounds could be used as fluorescence sensors and chiral recognition in different aggregating states. Chiral amine (1S,2R)-29formed in different states with the two enantiomers of the chiral acids. After the AIE compound27a was added, these chiral acids could be enantioselectively recognized and the enantiomer composition could also be quantitatively measured. The fluorescence intensity ratio of two enantiomers ranged from1.2to78.3. Chiral carboxylic acids35have been designed to enantioselectively self-assemble with two enantiomers chiral amine to form either nanofibers or nanospheres. The nanofibers exhibited stronger emission intensity and longer wavelengths of absorption and emission than the nanospheres. In the solution of water and THF, chiral carboxylic acids35a-f and chiral amine43could self-assemble to two different nanospheres with a hole or non-hole. Both nanospheres showed uptake and release capacity for the drug naproxen. The hollow nanospheres with a hole could absorb50%more naproxen than the non-hole nanospheres.4. The complexes included chiral carboxylic acids35and chiral amine43could be used as an organic template to introduce the tetraethyl silicate to form different structures and morphology silica oxide polymers with the Hydrolysis and Polycondensation reaction. Five different silica nanoparticles:hollow spheres, hollow spheres with a hole, helical nanoribbons, nanotubes with a hollow shell and square tubes could be synthesized through using these organic templates. A novel process of dissolving and re-assembling of template aggregates was the reason for forming a variety of morphologies of silica except square silica tubes which were directly controlled by template aggregates. The chirality of the template molecules played a key role in the formation mechanism of silica, the chirality of the silica nanoribbons and the silica morphology could be controlled by the chirality of the template molecules.5. A series of tetraphenylethene derivative51a-c and53a-c were synthesized, all of these compounds emit fluorescence both in solutions and aggregates states. They could interacted with γ-CD to form complexes with a ratio of1:1or1:2so that the fluorescence was quenched in a range of50%-88%, however, the fluorescence would not be quenched with the mixture of α-CD or β-CD. These complexes could be used for chiral recognition of1,2,3,4-tetrahedro-naphthoic acid and1,1’-bi-2-nanphthol. |
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