A5015127199- X-ray Diffraction in Crystallography
- Crystallization and Solubility Studies
- Catalytic Alkyne Reactions
- Catalytic C–H Functionalization Methods
- Cyclopropane Reaction Mechanisms
- Crystallography and molecular interactions
- Organometallic Complex Synthesis and Catalysis
- Metal complexes synthesis and properties
- Synthesis and Reactivity of Heterocycles
- Asymmetric Hydrogenation and Catalysis
- Synthesis of Organic Compounds
- Synthetic Organic Chemistry Methods
- Oxidative Organic Chemistry Reactions
- Synthesis and Characterization of Pyrroles
- Ferrocene Chemistry and Applications
- Magnetism in coordination complexes
- Hearing Loss and Rehabilitation
- Multicomponent Synthesis of Heterocycles
- N-Heterocyclic Carbenes in Organic and Inorganic Chemistry
- Lanthanide and Transition Metal Complexes
- 2D Materials and Applications
- Electrochemical sensors and biosensors
- Advanced Nanomaterials in Catalysis
- Catalytic Cross-Coupling Reactions
- Asymmetric Synthesis and Catalysis
City University of Hong Kong
2015-2025
Kowloon Hospital
2015-2020
MWT Materials (United States)
2018
State Key Laboratory of Millimeter Waves
2018
City University of Hong Kong, Shenzhen Research Institute
2017-2018
Chemical bonds, including covalent and ionic endow semiconductors with stable electronic configurations but also impose constraints on their synthesis lattice-mismatched heteroepitaxy. Here, the unique multi-scale van der Waals (vdWs) interactions are explored in one-dimensional tellurium (Te) systems to overcome these restrictions, enabled by vdWs bonds between Te atomic chains spontaneous misfit relaxation at quasi-vdWs interfaces. Wafer-scale nanomeshes composed of self-welding nanowires...
Isolation of the first examples Ru(II)–indoline and −indole zwitterion complexes derived from reactions between [Ru([14]aneS4)Cl2] ([14]aneS4 = 1,4,8,11-tetrathiacyclotetradecane) aniline-tethered alkynes has been achieved. Mechanistic studies regarding selectivity a “vinylidene-involving pathway” “direct nucleophilic ring closure mechanism” for these have conducted experimentally theoretically. Employment 1,2-silyl shift as strategy to lower activation barrier formation Ru–vinylidene...
Ruthenafuran and osmafuran monocationic complexes [Ru([14]aneS4)(C∧O)]+ or [M(bpy)2(C∧O)]+ (C∧O = anionic bidentate chelate [C(OR)CHC(Ph)═O]−; [14]aneS4 1,4,8,11-tetrathiacyclotetradecane; M Ru, Os; bpy 2,2′-bipyridine) have been prepared from reactions between phenyl-ynone HC≡C(CO)Ph [Ru([14]aneS4)Cl2] [M(bpy)2Cl2] in alcoholic solvents ROH. The formation of metal–vinylidene intermediate, followed by nucleophilic attack RO–, carbonyl group coordination to the metal center are believed be...
Cyclization of homopropargylic halopyridines on RuII/OsII centers leads to the formation cyclic Ru–/Os–halocarbon complexes with rare M−X−R bonding interactions, where metal center acts as a "molecular homewrecker" pull halogen atom from pyridyl ring. This interaction highlights importance metal–halocarbon bonds in catalytic and coordination design. More details are available Research Article by C.-Y. Wong co-workers (DOI: 10.1002/chem.202403736).
Indolizine zwitterion coordinated metal species have been commonly proposed as intermediates in the mechanisms of metal-catalyzed cycloisomerization propargylic pyridines for indolizines. Yet, it is only recently that first metal–indolizine complexes isolated by our group. Considering from perspective molecular materials, π-interaction between dπ(M) and π-system indolizine skeleton electronic ground or excited states may allow charge delocalization offer functionalities optoelectronic...
Abstract Metallafuran complexes with a fused five‐membered phosphonium ring were synthesized from reactions between terminal ynones HC≡C(C=O)R and cis ‐[Ru/Os(dppm) 2 Cl ] (dppm=1,1‐bis(diphenylphosphino)methane). A metal–vinylidene‐involving pathway was found to be an energetically feasible formation mechanism for these complexes. These phosphonium‐containing metallafurans, like many phosphonium‐functionalized drugs, have the ability induce mitochondrial dysfunction. They also exhibit...
Abstract The two families of Ru II ‐chromene and ‐chromone complexes isolated in this work represent the first examples metalated chromene chromone synthesized through transition‐metal‐mediated cyclization phenol‐tethered ynone. These unprecedented heterocyclic compounds exhibit remarkable features, such as pH‐switchable metal–carbon bonding interactions, photo‐triggerable release organic upon visible‐light irradiation, superior antioxidative property to their analogue (1,4‐benzopyrone)....
Indolizine-fused metallafuran and metal–quinolizinium complexes were synthesized from reactions between dipicolinyl-substituted propargylic alcohol HC≡CC(OH)(CH2(2-py))2 cis-[Ru/Os(dppm)2Cl2] (dppm = 1,1-bis(diphenylphosphino)methane), revealing the operation of both non-vinylidene vinylidene pathways regarding Ru(II)/Os(II)–alkyne interactions. Strategies to control selectivity these two competitive successfully developed, paving ways rational design Ru/Os-induced alkyne activations metallacycles.
The two series of ruthenium-indolizinone complexes prepared by Ru-mediated cyclization pyridine-tethered alkynes represent the first examples metalated indolizinone complexes. Joint experimental-theoretical investigation suggests an unconventional 5-endo-dig pathway as their formation mechanism. They also exhibit moderate cytotoxicity against several human cancer cell lines.
Isolation of the C3-metalated indolizine and bicyclic osmafuran complexes revealed intermediacy metal–vinylidene species regarding [Os(dppm)<sub>2</sub>Cl]<sup>+</sup>-mediated alkyne transformations.
Two types of unexpected quinolizinium complexes were obtained from the reactions between pyridine-functionalized propargylic alcohol HCCC(OH)(Ph)(CH<sub>2</sub>(2-py)) (<bold>L1</bold>) and <italic>cis</italic>-[M(L^L)<sub>2</sub>Cl<sub>2</sub>] (M = Ru, Os; L^L dppm, bpy).
Diphosphine-containing Ru(II)/Os(II)–chromene and −chromone complexes were synthesized from reactions between phenol ynone HC≡C(C═O)(o-C6H4OH) cis-[Ru/Os(dppm)2Cl2] (dppm = 1,1-bis(diphenylphosphino)methane). The structures of these in the solid state along with their pH-dependent chromene/chromone equilibrium behavior aqueous medium investigated. cis–trans equilibration solution demonstrated by chloride-ligated Ru–chromene series represents a rare example for Ru bearing dppm auxiliary...
Reactions between pyridine-functionalized alkynes and an Fe(ii) precursor supported by 2,5,8-trithia[9](2,9)-1,10-phenanthrolinophane afforded the first Fe(ii)-indolizine -indolizinone complexes. Structural analysis theoretical calculations revealed existence of unconventional "non-vinylidene" pathways challenged generality vinylidene intermediacy in Fe(ii)-induced alkyne transformations.
Mononuclear and dinuclear Ru(II) complexes cis-[Ru(κ2-dppm)(bpy)Cl2] (1), cis-[Ru(κ2-dppe)(bpy)Cl2] (2) [Ru2(bpy)2(μ-dpam)2(μ-Cl)2](Cl)2 ([3](Cl)2) were prepared from the reactions between cis(Cl), cis(S)-[Ru(bpy)(dmso-S)2Cl2] diphosphine/diarsine ligands (bpy = 2,2'-bipyridine; dppm 1,1-bis(diphenylphosphino)methane; dppe 1,2-bis(diphenylphosphino)ethane; dpam 1,1-bis(diphenylarsino)methane). While methoxy-substituted ruthenafuran [Ru(bpy)(κ2-dppe)(C^O)]+ ([7]+; C^O anionic bidentate...
Systematic investigations on the reactions between cis-[M(dppm)2 Cl2 ] (M=Ru/Os; dppm=1,1-bis(diphenylphosphino)methane) and pyridine/quinoline substituted homopropargylic alcohols uncovered diverse Ru(II)/Os(II)-induced alkyne activation pathways. The alkynes underwent cyclization M via a "non-vinylidene" pathway at lower temperatures, resulting in alkenyl intermediates which might further metallacyclize to give metallapyrroloindolizines. Conversely, higher temperatures induced "vinylidene"...
Abstract The activation of various homopropargylic pyridines by cis ‐[Ru II /Os (dppm) 2 Cl ] (dppm=1,1‐bis(diphenylphosphino)methane) has previously been shown to generate a diverse array metallacycles and metalated heterocyclic complexes. However, minor structural modification introducing halide onto the pyridyl group alkyne substrate resulted in formation unprecedented Ru(II)/Os(II)−haloquinolizine These complexes display (1) κ ( X , C )‐haloquinolizine chelates arising from...
A new tetradentate mixed aza-thioether macrocyclic ligand 2,6-dithia[7](2,9)-1,10-phenanthrolinophane ([13]ane(phenN2)S2) was successfully synthesized. Reacting metal precursors [Fe(CH3CN)2(OTf)2], Ni(ClO4)2·6H2O, and Cu(ClO4)2·6H2O with one equivalent of [13]ane(phenN2)S2 afforded [Fe([13]ane(phenN2)S2)(OTf)2] (1), [Ni([13]ane(phenN2)S2)](ClO4)2 (2(ClO4)2), [Cu([13]ane(phenN2)S2)(OH2)](ClO4)2 (3(ClO4)2), respectively. The structures all its complexes were investigated by X-ray...
Rhodium(III) complexes containing tridentate N‐heterocyclic carbene (NHC)‐based pincer ligand in the form of [Rh(C ^ N C)(N N)X] 2+ and C)(tpy)] 3+ (C C = (2,6‐bis(1‐butylimidazol‐2‐ylidene)pyridine 1 ) or 2,6‐bis(3‐butylbenzimidazol‐2‐ylidene)pyridine 2 ); bipyridine‐type aromatic diimines; tpy 2,2':6',2''‐terpyridine; X Cl Br) were prepared. Spectroscopic comparisons time‐dependent density functional theory (TD‐DFT) calculations revealed lowest‐energy electronic transition associated with...