Qingkai Yuan

Mr. Qingkai Yuan


Research Focus & Metrics

Academic Career Length

3Years (2024-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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11 May 2024 in Molecules
Verified
Journal Article
Open access
PDF file
TXTing Xu
Ting Xu
JWJia-Yin Wang
Jia-Yin Wang
YWYu Wang
Yu Wang
SJShengzhou Jin
Shengzhou Jin
YTYao Tang
Yao Tang
GLGuigen Li
Guigen Li
In this study, the design and asymmetric synthesis of a series of chiral targets of orientational chirality were conducted by taking advantage of N-sulfinylimine-assisted nucleophilic addition and modified Sonogashira catalytic coupling systems. Orientational isomers were controlled completely using alkynyl/alkynyl levers [C(sp)-C(sp) axis] with absolute configuration assignment determined by X-ray structural analysis. The key structural element of the resulting orientational chirality is uniquely characterized by remote through-space blocking. Forty examples of multi-step synthesis were performed, with modest to good yields and excellent orientational selectivity. Several chiral orientational amino targets are attached with scaffolds of natural and medicinal products, showing potential pharmaceutical and medical applications in the future.

29 January 2025 in Molecules
Verified
Journal Article
Open access
PDF file
YWYu Wang
Yu Wang
TXTing Xu
Ting Xu
APAnkit Pandey
Ankit Pandey
SJShengzhou Jin
Shengzhou Jin
JYJasmine X. Yan
Jasmine X. Yan
GLGuigen Li
Guigen Li
Enantiopure turbo chirality in small organic molecules, without other chiral elements, is a fascinating topic that has garnered significant interest within the chemical and materials science community. However, further research into and application of this concept have been severely limited by the lack of effective asymmetric tools. To date, only a few enantiomers of turbo chiral targets have been isolated, and these were obtained through physical separation using chiral HPLC, typically on milligram scales. In this work, we report the first asymmetric approach to enantiopure turbo chirality in the absence of other chiral elements such as central and axial chirality. This is demonstrated by assembling aromatic phosphine oxides, where three propeller-like groups are anchored to a P(O) center via three axes. Asymmetric induction was successfully carried out using a chiral sulfonimine auxiliary, with absolute configurations and conformations unambiguously determined by X-ray diffraction analysis. The resulting turbo frameworks exhibit three propellers arranged in either a clockwise (P,P,P) or counterclockwise (M,M,M) configuration. In these arrangements, the bulkier sides of the aromatic rings are oriented toward the oxygen atom of the P=O bond rather than in the opposite direction. Additionally, the orientational configuration is controlled by the sulfonimine auxiliary as well, showing that one of the Naph rings is pushed away from the auxiliary group (-CH2-NHSO2-tBu) of the phenyl ring. Computational studies were conducted on relative energies for the rotational barriers of a turbo target along the P=O axis and the transition pathway between two enantiomers, meeting our expectations. This work is expected to have a significant impact on the fields of chemistry, biomedicine, and materials science in the future.

24 June 2024 in ChemRxiv
Verified
Preprint
Open access
PDF file
SZSai Zhang
Sai Zhang
QYQingkai Yuan
Qingkai Yuan
YWYu Wang
Yu Wang
YTYao Tang
Yao Tang
ARAnis Ur Rahman
Anis Ur Rahman
GLGuigen Li
Guigen Li
It is well-known that racemic molecules are elliptically inactive. Herein, we found novel racemic multilayer polymers and oligomers that are generated from catalytic polymerization can asymmetrically rotate the plane-polarized circular light to the right-handed direction in THF-H2O cosolvents. The specific rotation depends on the water ratios (fw) of co-solvents and UV-vis radiation time inside polarimeter. The aggregation of polymers and oligomers was proven via AIE (aggregation-induced emission) appeared as they dissolved in THF-H2O co-solvents, which would be responsible for this abnormal phenomenon. This discovery is anticipated to lead to a new research topic in chemical, medical, and materials sciences, and provide an alternative clue to the origin of life on earth in the future.