Jiangxi Key Laboratory of Organic Chemistry, Jiangxi Science and Technology Normal University, Nanchang 330013, China.
State Key Laboratory of Molecular Engineering of Polymers, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials iChEM, Department of Chemistry, Fudan University, Shanghai 200433, China.
Int J Mol Sci. 2024 May 21;25(11):5606. doi: 10.3390/ijms25115606.
The chiral H-BINOL derivatives R- and R- were efficiently synthesized via a Suzuki coupling reaction, and they can be used as novel dialdehyde fluorescent probes for the enantioselective recognition of R/S-2-amino-1-phenylethanol. In addition, R- is much more effective than R-. Scanning electron microscope images and X-ray analyses show that R- can form supramolecular vesicles through the self-assembly effect of the π-π force and strong hydrogen bonding. As determined via analysis, the fluorescence of the probe was significantly enhanced by mixing a small amount of S-2-amino-1-phenylethanol into R-, with a redshift of 38 nm, whereas no significant fluorescence response was observed in R-2-amino-1-phenylethanol. The enantioselective identification of S-2-amino-1-phenylethanol by the probe R- was further investigated through nuclear magnetic titration and fluorescence kinetic experiments and DFT calculations. The results showed that this mechanism was not only a simple reactive probe but also realized object recognition through an ICT mechanism. As the intramolecular hydrogen bond activated the carbonyl group on the probe R-, the carbonyl carbon atom became positively charged. As a strong nucleophile, the amino group of S-2-amino-1-phenylethanol first transferred the amino electrons to a carbonyl carbocation, resulting in a significantly enhanced fluorescence of the probe R- and a 38 nm redshift. Similarly, S-2-amino-1-phenylethanol alone caused severe damage to the self-assembled vesicle structure of the probe molecule itself due to its spatial structure, which made R- highly enantioselective towards it.
手性 H-BINOL 衍生物 R-和 R-通过 Suzuki 偶联反应高效合成，可作为新型二醛荧光探针，对 R/S-2-氨基-1-苯乙醇进行对映选择性识别。此外，R-比 R-更有效。扫描电子显微镜图像和 X 射线分析表明，R-可以通过π-π 力和氢键的自组装效应形成超分子囊泡。通过分析表明，探针 R-中少量 S-2-氨基-1-苯乙醇的混合使荧光显著增强，红移 38nm，而 R-2-氨基-1-苯乙醇则没有明显的荧光响应。探针 R-对 S-2-氨基-1-苯乙醇的对映选择性识别通过核磁共振滴定和荧光动力学实验以及 DFT 计算进一步研究。结果表明，该机制不仅是一种简单的反应性探针，而且通过 ICT 机制实现了客体识别。由于分子内氢键激活了探针 R-上的羰基，羰基碳原子带正电荷。作为强亲核试剂，S-2-氨基-1-苯乙醇的氨基首先将氨基电子转移到羰基碳正离子上，导致探针 R-的荧光显著增强，红移 38nm。同样，由于其空间结构，S-2-氨基-1-苯乙醇本身对探针分子自组装囊泡结构造成严重破坏，使其对 R-具有高度的对映选择性。
