Article
Chemistry, Organic
Daniel V. Schiavone, Joel Gallardo, Diana M. Kapkayeva, John-Charles Baucom, Ryan P. Murelli
Summary: This manuscript describes a new class of fluorescent small molecules based on lactam-fused tropolones that are responsive to a dynamic range of environmental changes. These molecules can be easily obtained through a rapid annulation procedure and exhibit fluorescence emission across the visible light spectra, with tunable properties based on the tropolone or amine component.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2023)
Article
Spectroscopy
Essam M. Hussein, Nizar El Guesmi, Saleh A. Ahmed
Summary: The study extensively investigated the photophysical properties of 24 environmentally-sensitive cyanopyridine fluorophores in various solvents, revealing the fluorescence behavior, quantum yield, and Stokes shifts. Different para-substituted-phenyl moieties were also found to affect the emission spectra sensitivity. The analysis using Lippert-Mataga and Reichardts correlations further suggested the strong ICT character of the designed fluorescence derivatives.
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
(2021)
Article
Chemistry, Multidisciplinary
Xiaoqiang Yan, Jijun Jiang, Jun Wang
Summary: In this study, an unusual class of planar-chiral rhodium catalysts bearing non-chiral Cp ligands was described. These catalysts are readily tunable and were successfully used in enantioselective C-H activation reactions, showing great potential in this field.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Biochemical Research Methods
Matt Timmers, Jimmy Weterings, Michiel Van Geijn, Roel Bell, Peter E. Lenting, Cristianne J. F. Rijcken, Tina Vermonden, Wim E. Hennink, Rob M. J. Liskamp
Summary: Core-cross-linked polymeric micelles (CCPMs) are a promising nanoparticle platform for sustained drug release. This study investigates the suitability of trityl-based linkers for acid-triggered release of active pharmaceutical ingredients (APIs) from CCPMs, and finds that the reaction mechanism of trityl deprotection plays an important role in the API release kinetics.
BIOCONJUGATE CHEMISTRY
(2022)
Article
Chemistry, Applied
Xu-Li Miao, Wei Feng, Qin-Hua Song
Summary: In this study, three electron donor-acceptor fluorescent probes were developed for rapid detection of phosgene. Among them, probe 2a showed the fastest response time (5 s), the lowest limit of detection (1.4 nM), and significant fluorescence change from green to bright blue in solution. Test strips fabricated with probe 2a exhibited good selectivity and sensitivity for phosgene detection in the gas phase.
Article
Chemistry, Multidisciplinary
Jingqi Han, Yuen-Kiu Chun, Shing-Lun Chan, Shun-Cheung Cheng, Shek-Man Yiu, Chi-Chiu Ko
Summary: A new series of Ir(III) carbene complexes with luminescent mechanochromism derived from transcis isomerization have been developed. The introduction of p-conjugating groups into the acyclic carbene ligand allows for easy interconversion between mechanochromic trans- and cis-configurations, resulting in dual emissive properties in the solid state. The solvent system used for solid- or film-forming can control the dual emission and mechanoresponsive properties. The potential uses of a single emissive complex to develop multicolor emissive and multiple stimuli-responsive films have been studied.
Article
Chemistry, Physical
Ruoyang Liu, Shun-Cheung Cheng, Yelan Xiao, Kin-Cheung Chan, Ka-Ming Tong, Chi-Chiu Ko
Summary: Recyclable heterogeneous catalysts with dual emissive properties have been developed by anchoring cyclometalated Ir (III) complexes on polymer support materials. These catalysts show excellent recyclability and have been studied for their photocatalytic activity.
JOURNAL OF CATALYSIS
(2022)
Article
Chemistry, Multidisciplinary
Jing Xiang, Yi Pan, Lu-Lu Liu, Li-Xin Wang, Huan Yang, Shun-Cheung Cheng, Shek-Man Yiu, Chi-Fai Leung, Chi-Chiu Ko, Kai-Chung Lau, Tai-Chu Lau
Summary: Although the oxidation of alcohols by metal nitrido complexes has not been studied extensively, this report demonstrates the visible-light-induced oxidation of primary and secondary alcohols to carbonyl compounds using a strongly luminescent osmium(VI) nitrido complex (OsN). The proposed mechanism involves the rate-limiting hydrogen-atom transfer from the alpha-carbon of the alcohol to OsN*. Attempts to catalytically oxidize alcohols by OsN* using PhIO as the terminal oxidant resulted in the formation of novel osmium(IV) iminato complexes where the nitrido ligand is bonded to a 6-carbon of the alcohol. Experimental and theoretical studies suggest that OsN* is reductively quenched by PhIO to generate highly active PhIO+ oxidant, which readily undergoes alpha- and 6- C-H activation of alcohols.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Multidisciplinary
Wing-Kei Kwok, Lok-Kwan Li, Shiu-Lun Lai, Ming-Yi Leung, Wai Kit Tang, Shun-Cheung Cheng, Man-Chung Tang, Wai-Lung Cheung, Chi-Chiu Ko, Mei-Yee Chan, Vivian Wing-Wah Yam
Summary: A new class of gold(III) complexes containing acridinyl moieties and tetradentate C<^>C<^>N<^>N ligand has been designed and synthesized, which exhibit high photoluminescence quantum yields in solid-state thin films. These complexes have been utilized to fabricate high-performance OLEDs with high external quantum efficiencies and satisfactory operational half-lifetime values. The TADF properties of the complexes have been substantiated by various experimental techniques.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Chemistry, Inorganic & Nuclear
Rain Ng, Shun-Cheung Cheng, Ka-Lok Chan, Cheuk-Pui Leung, Wai-Man Cheung, Herman H. -Y. Sung, Hung Kay Lee, Chi-Chiu Ko, Ian D. Williams, Zhenyang Lin, Wa-Hung Leung
Summary: In this study, iridium complexes containing a bis-cyclometalated tripodal CANAC ligand were synthesized and their redox property and reactivity were investigated. Various iridium complexes were successfully obtained through different reactions, and their structures and properties were further studied. The results highlighted the crucial role of the CANAC ligand in stabilizing high-valent iridium.
Article
Chemistry, Physical
Pui-Yu Ho, Shun-Cheung Cheng, Fei Yu, Yau-Yuen Yeung, Wen-Xiu Ni, Chi-Chiu Ko, Chi-Fai Leung, Tai-Chu Lau, Marc Robert
Summary: We present an efficient visible light-driven CO2 reduction system that operates in water without the use of noble metals or rare materials. By employing a cobalt complex as a catalyst, an organic triazatriangulenium salt as a photosensitizer, and BIH + TEOA as a sacrificial reductant, we achieved CO and formate production with high selectivity and total turnover numbers exceeding 3700. The addition of a weak Brönsted acid further improved the catalysis, resulting in a selectivity of 93% and a total turnover number of 19,000 for CO production. The photocatalytic system demonstrated excellent performance even in pure water, with a turnover number of 2600 and a selectivity of 94% using TEA as the sacrificial reductant.
Review
Chemistry, Analytical
Ruoyang Liu, Chi-Chiu Ko
Summary: MIP-based luminescent chemosensors have been widely studied due to their high specificity and sensitivity in molecular recognition and luminescence detection. Different strategies, including incorporation of luminescent functional monomers and surface-imprinting polymerization on luminescent nanomaterials, have been used to construct luminescent MIPs for various analytes. This review discusses the design strategies, sensing approaches, and applications of luminescent MIP-based chemosensors in biosensing, bioimaging, food safety, and clinical diagnosis, as well as the limitations and prospects for future development.
Article
Chemistry, Physical
Yelan Xiao, Yecheng Leng, Xinxin Lu, Shun-Cheung Cheng, Hao Huang, Man-Kit Tse, Jiechun Liang, Wenguang Tu, Chi-Chiu Ko, Xi Zhu, Lu Wang, Yong Zhou, Yingfang Yao, Zhigang Zou
Summary: Photocatalytic radical fluoroalkylation is an important method to prepare organofluorine compounds. This study introduces a cost-effective and recyclable heterogeneous photocatalysis using cyano-modified graphitic carbon nitride as the photocatalyst. The photocatalytic process is attributed to the long-lived triplet excited states and the strong interaction between the catalyst and substrate. Moreover, the catalyst shows high performance, wide reaction scope, and can be easily recovered and reused for multiple catalytic cycles.
JOURNAL OF CATALYSIS
(2023)
Article
Chemistry, Inorganic & Nuclear
Yongyi Feng, Shun-Cheung Cheng, Chi-Chiu Ko
Summary: In this study, a cyanopentafluorophosphate ligand with exceptional pi-accepting ability was synthesized, showing promise in the design of fluorescent materials and catalysts.
JOURNAL OF ORGANOMETALLIC CHEMISTRY
(2023)
Article
Engineering, Marine
Yi Yang, Tze W. Chow, Yi Q. Zhang, Peter K. N. Yu, Chi C. Ko, Rudolf S. S. Wu
Summary: Existing methods for monitoring radionuclides in aquatic environments are often impractical due to the need for frequent sampling and tedious analytical procedures. This study explored the feasibility of using 'Artificial Mussels' (AMs) as a new tool for radionuclide monitoring in marine environments. Results showed that AMs could effectively accumulate U-238, Sr-88, and Cs-133 from water, reaching equilibrium within 7 to 8 weeks with high concentration factors. These findings suggest that AMs can overcome the limitations of existing methods and offer a practical solution for radionuclide monitoring.
JOURNAL OF MARINE SCIENCE AND ENGINEERING
(2023)
Review
Chemistry, Multidisciplinary
Shing-Lun Chan, Yuen-Kiu Chun, Chi-Chiu Ko
Summary: Transition-metal acyclic carbene complexes have gained attention due to their comparable properties with N-heterocyclic carbene (NHC) ligands. These complexes show outstanding performance and functional properties, making them alternatives to NHC complexes for developing metal-based functional materials. The substituents and micro-environment significantly affect their structure and electronic properties, allowing for varied functional properties through rational molecular design. They are also suitable for stimuli-responsive materials and chemical sensors. This article describes the preparation, electronic properties, and design of metal acyclic carbene complexes for advanced materials development.
MATERIALS CHEMISTRY FRONTIERS
(2023)
Article
Chemistry, Inorganic & Nuclear
Ruoyang Liu, Shun-Cheung Cheng, Chi-On Ng, Yelan Xiao, Kin-Man Tang, Ka-Ming Tong, Ngai-Yu Lei, Chi-Chiu Ko
Summary: A luminescent sensor for detecting trimethylamine (TMA) has been developed using a polymer with immobilized phosphorescent material. The sensor can rapidly and selectively detect TMA in both aqueous solutions and gaseous states, with low detection limits.
DALTON TRANSACTIONS
(2023)
Article
Chemistry, Inorganic & Nuclear
Li-Xin Wang, Shun-Cheung Cheng, Yingying Liu, Chi-Fai Leung, Ji-Yan Liu, Chi-Chiu Ko, Tai-Chu Lau, Jing Xiang
Summary: A series of new copper(I) complexes have been synthesized and characterized. These complexes exhibit tunable emission spectra in solution and their molecular structures have been determined by X-ray crystallography. Density functional theory calculations reveal the characteristics of these complexes.
DALTON TRANSACTIONS
(2023)
Article
Chemistry, Multidisciplinary
Cathay Chai Au-Yeung, Ming-Yi Leung, Shiu-Lun Lai, Shun-Cheung Cheng, Lok-Kwan Li, Man-Chung Tang, Wing-Kei Kwok, Chi-Chiu Ko, Mei-Yee Chan, Vivian Wing-Wah Yam
Summary: A new class of gold(III) complexes with pyridine-/pyrazine-containing tetradentate ligands has been synthesized and characterized. These complexes exhibit high photoluminescence quantum yields in solid-state thin films and a significant increase in radiative decay rate constant upon increasing temperature. The activation parameters and energy separation values between excited states were determined. Furthermore, strategic modification of the ligand structure can enhance the alignment of the emitting layer and improve the efficiency and performance of organic light-emitting devices.
MATERIALS HORIZONS
(2023)
Article
Chemistry, Inorganic & Nuclear
Ruoyang Liu, Shun-Cheung Cheng, Chi-On Ng, Yelan Xiao, Kin-Man Tang, Ka-Ming Tong, Ngai-Yu Lei, Chi-Chiu Ko
Summary: A luminescent TMA sensor, PTMA-Ir, was developed by immobilizing a phosphorescent iridium complex on a TMA-imprinted polymer. The quenching of PTMA-Ir's phosphorescence could be used as a reporter for TMA binding, allowing for sensitive and selective detection of TMA in aqueous solutions and gaseous states. A deposition T-Ir loaded on filter paper showed a rapid quenching of phosphorescence upon exposure to TMA vapor, with low detection limits in both argon and air atmospheres.
DALTON TRANSACTIONS
(2023)
