Uyen P. N. Tran

Bio: Uyen P. N. Tran is an academic researcher from Văn Hiến University. The author has contributed to research in topics: Medicine & Kinetics. The author has an hindex of 7, co-authored 13 publications receiving 599 citations. Previous affiliations of Uyen P. N. Tran include University of New South Wales & Ho Chi Minh City University of Technology.

Expanding Applications of Metal−Organic Frameworks: Zeolite Imidazolate Framework ZIF-8 as an Efficient Heterogeneous Catalyst for the Knoevenagel Reaction

Abstract: A highly porous zeolite imidazolate framework (ZIF-8) was synthesized by a solvothermal method, and used as an efficient heterogeneous catalyst for the Knoevenagel reaction. The solid catalyst was characterized using a variety of different techniques, including X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), dynamic laser light scattering (DLS), thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FT-IR), atomic absorption spectrophotometry (AAS), and nitrogen physisorption measurements. Quantitative conversion was achieved under mild conditions. The ZIF-8 catalyst could be facilely separated from the reaction mixture, and could be reused without significant degradation in catalytic activity. Furthermore, no contribution from homogeneous catalysis of active species leaching into reaction solution was detected.

Tropylium-promoted carbonyl–olefin metathesis reactions

Abstract: The carbonyl–olefin metathesis (COM) reaction is a highly valuable chemical transformation in a broad range of applications. However, its scope is much less explored compared to analogous olefin–olefin metathesis reactions. Herein we demonstrate the use of tropylium ion as a new effective organic Lewis acid catalyst for both intramolecular and intermolecular COM and new ring-opening metathesis reactions. This represents a significant improvement in substrate scope from recently reported developments in this field.

Carbonyl–Olefin Metathesis Catalyzed by Molecular Iodine

Abstract: The carbonyl–olefin metathesis reaction could facilitate rapid functional group interconversion and allow construction of complicated organic structures. Herein, we demonstrate that elemental iodine, a very simple catalyst, can efficiently promote this chemical transformation under mild reaction conditions. Our mechanistic studies revealed intriguing aspects of the activation mode via molecular iodine and the iodonium ion that could change the previously established perception of catalyst and substrate design for the carbonyl–olefin metathesis reaction.

Catalytic Synthesis of Trifluoromethyl Cyclopropenes and Oligo‐Cyclopropenes

Abstract: The synthesis of trifluoromethylated cyclopropenes is often associated with important applications in drug discovery and functional materials. In this report, we describe the use of readily available chiral rhodium(II) catalysts for a highly efficient asymmetric cyclopropenation reaction of fluorinated donor-acceptor diazoalkanes with a broad variety of aliphatic and aromatic alkynes. Further studies highlight the unique reactivity of fluorinated donor-acceptor diazoalkanes in the synthesis of oligo-cyclopropenes. Subsequent C-H functionalization of trifluoromethyl cyclopropenes furnishes densely substituted cyclopropene frameworks and also allows the alternative synthesis of bis-cyclopropenes.

Metal-Organic Frameworks for Heterogeneous Basic Catalysis.

Abstract: Great attention has been given to metal–organic frameworks (MOFs)-derived solid bases because of their attractive structure and catalytic performance in various organic reactions. The extraordinary skeleton structure of MOFs provides many possibilities for incorporation of diverse basic functionalities, which is unachievable for conventional solid bases. The past decade has witnessed remarkable advances in this vibrant research area; however, MOFs for heterogeneous basic catalysis have never been reviewed until now. Therefore, a review summarizing MOFs-derived base catalysts is highly expected. In this review, we present an overview of the recent progress in MOFs-derived solid bases covering preparation, characterization, and catalytic applications. In the preparation section, the solid bases are divided into two categories, namely, MOFs with intrinsic basicity and MOFs with modified basicity. The basicity can originate from either metal sites or organic ligands. Different approaches used for generation o...

Catalysis by metal nanoparticles embedded on metal–organic frameworks

Abstract: The present review describes the use of metal–organic frameworks (MOFs) as porous matrices to embed metal nanoparticles (MNPs) and occasionally metal oxide clusters, which are subsequently used as heterogeneous catalysts. The review is organized according to the embedded metal including Pd, Au, Ru, Cu, Pt, Ni and Ag. Emphasis is also given in the various methodologies reported for the formation of the NPs and the characterization techniques. The reactions described with this type of solid catalysts include condensation, hydrogenations, carbon–carbon coupling, alcohol oxidations and methanol synthesis among others. Remaining issues in this field have also been indicated.

Zeolitic imidazolate framework materials: recent progress in synthesis and applications

Abstract: Zeolitic imidazolate frameworks (ZIFs) represent a new and special class of metal organic frameworks comprised of imidazolate linkers and metal ions, with structures similar to conventional aluminosilicate zeolites Their intrinsic porous characteristics, abundant functionalities as well as exceptional thermal and chemical stabilities have led to a wide range of potential applications for various ZIF materials Explosive research activities ranging from synthesis approaches to attractive applications of ZIFs have emerged in this rapidly developing field in the past 5 years In this review, the development and recent progress towards different synthesis strategies to generate both powder and membrane/film-based ZIF materials are analysed and summarised Their attractive and potential applications in gas separation, catalysis, sensing and electronic devices, and drug delivery in the past years are discussed and reviewed In addition, the prospects and potential new development of ZIF materials are presented

Semiconductor@Metal–Organic Framework Core–Shell Heterostructures: A Case of ZnO@ZIF-8 Nanorods with Selective Photoelectrochemical Response

Abstract: Metal–organic frameworks (MOFs) and related material classes are attracting considerable attention for their applications in gas storage/separation as well as catalysis In contrast, research concerning potential uses in electronic devices (such as sensors) is in its infancy, which might be due to a great challenge in the fabrication of MOFs and semiconductor composites with well-designed structures In this paper, we proposed a simple self-template strategy to fabricate metal oxide semiconductor@MOF core–shell heterostructures, and successfully obtained freestanding ZnO@ZIF-8 nanorods as well as vertically standing arrays (including nanorod arrays and nanotube arrays) In this synthetic process, ZnO nanorods not only act as the template but also provide Zn2+ ions for the formation of ZIF-8 In addition, we have demonstrated that solvent composition and reaction temperature are two crucial factors for successfully fabricating well-defined ZnO@ZIF-8 heterostructures As we expect, the as-prepared ZnO@ZIF-8