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============================================================== 제 목 : Preparation of superhydrophobic/superoleophilic sponge and steel mesh for rapid oil/water separation 연 사 : Prof. Saeid Azizian(Bu-Ali Sina University) 일 시 : 2018년 8월 23일(목) 오후 4시 30분 장 소 : 화학관 2층 서병인강의실(330226호실) ============================================================== Preparation of superhydrophobic/superoleophilic sponge and steel mesh for rapid oil/water separation In recent years, with the development of economy and society the frequent occurrence of water pollution by oil spillages and organic-compounds leakages has caused severe environmental and ecological problems. Therefore, oil-water separation has been a global challenge. The traditional methods or materials for oil/water separation such as in situ burning, gravity separation, air flotation, bioremediation and adsorption usually showed low separation efficiency, poor separation selectivity, high energy consumption as well as high operational complexity. Recently, surfaces with superhydrophobic and superoleophilic wettability (with water contact angle greater than 150°) which achieved by constructing rough surfaces and modifying with low-surface energy materials have attracted great interesting in the field of filtration. Herein a facile method, for the preparation of highly hydrophobic and highly oleophilic sponge and steel mesh will be presented which can be successfully used for effective oil-spill cleanup and oil/water filtration.
============================================================== 제 목 : BoShinTang (Healthy Soup) and Ssam (Wrap): Teaching Strategies for Professors of Diverse Young Chemists 연 사 : 윤지윤 교수님(University of Texas Arlington) 일 시 : 2018년 6월 14일(목) 오후 4시 장 소 : 화학관 2층 서병인강의실(330226호실) ============================================================== BoShinTang (Healthy Soup) and Ssam (Wrap): Teaching Strategies for Professors of Diverse Young Chemists Abstract As student population grows more diverse in post-secondary institutions, it is facing greater challenges in delivering instruction that provides effective care of the diverse student population, which includes those who speak English as a second language. This presentation introduces two instructional strategies, “Inclusive and Flipped Classroom,” that is designed for professors of the diverse young chemists to address their needs with a variety of backgrounds, learningstyles, and abilities. For the Inclusive classroom, the audience will learn various instructional strategies with examples, especially for culturally-responsive instructions. For the flipped classroom, the audience will be provided by one case study using an asynchronous tool, “VoiceThread.” By using these new instructional approaches, the professors will be enable to create equal educational opportunities for and improve the academic attainment in Chemistry for their diverse young chemists. Also, these new approaches will increase the professors’ interests in multicultural education. By applying the needs of ethnically diverse students into teaching, professors enhance theirknowledge and understanding of other cultures. Therefore, this presentation will advance the quality of university education for diverse students and help them to achieve their degrees by building institutional capacity for preparing a professional workforce, broadening their participation in Chemistry, and fostering all the students to complete their degrees in higher education.
============================================================== 제 목 : Understanding of alumina surface properties and catalyst preparation 연 사 : 곽자훈 교수님(School of Energy and Chemical Engineering, UNIST) 일 시 : 2018년 5월 31일(목) 오후 4시 30분 장 소 : 화학관 2층 세미나실(330226호실) ============================================================== Understanding of alumina surface properties and catalyst preparation Ja Hun Kwak School of Energy and Chemical Engineering, UNIST (jhkwak@unist.ac.kr) Alumina is one of the most important heterogeneous catalyst materials, and is mainly used as a support for catalytically active phases (metal and oxide) owing to its surface properties, such as high surface area and thermal stability. Al2O3-based catalysts have wide applications, ranging from petroleum chemistry to automobile emission control. In addition, alumina itself is a well-known acidic catalyst for alcohol dehydration reactions. In this presentation, I would like to show the recent results that the surface properties of alumina characterized using ethanol TPD and ethanol dehydration reactions. Based on these results, I suggest that the ethanol interaction as a general descriptor of alumina surfaces. And I also utilize these quantitative understanding of alumina surface properties for understanding how does the catalytic materials interact with alumina surfaces. These results will provide important guidelines for the synthesis and characterization of commercially important alumina-supported catalysts. Keywords: alumina surface, acid-base property, alcohol dehydration, ethanol-TPD, Pt on alumina
============================================================== 제 목 : Chemistry-oriented synthesis of drug scaffolds and chemo-centric target profiling of the scaffolds 연 사 : 김미현 교수님(가천대학교 약학과) 일 시 : 2018년 5월 10일(목) 오후 4시 30분장 소 : 화학관 2층 세미나실(330226호실) ============================================================== Chemistry-oriented synthesis of drug scaffolds and chemo-centric target profiling of the scaffolds Arramshetti Venkanna, Zakir Ullah, Sualiha Afzal, Kang Kim, andMi-hyun Kim* Department of Pharmacy, College of Pharmacy, Gachon University, Hambakmoeiro 191, Yeonsu-gu, Incheon, Republic of Korea Can researchers simultaneously consider academic interest and the integrated platform of ‘from bench to market, and from market to bench’ during their drug R&D process? For the purpose, which type of factors need to be considered? Among current feasible factors, chemists in drug R&D can choose structural novelty of drug for IP transfer. In the contrast to the factor, current dominant strategy of drug discovery is rational drug design against a determined novel target (disease, MOA, pathway, or protein) and the strategy can exclude structural novel compounds due to weak activity towards the target. However, regardless of the main strategy, chemists can wonder how to maximize the utility of their new compounds as like drug repositioning of a clinical drug in drug discovery. In my study, the drug discovery ‘from curiosity in chemical structure, itself of drug scaffold’ rather than ‘from a specific target’ was considered. As an example, synthetic methodology of a novel drug scaffold, anomeric N,N-diarylamino tetrahydropyran was developed through C(sp3)-H functionalized cross-dehydrogenative coupling of aminoalochol under non-metal condition (TEMPO/iodine, TEMPO/ trivalent iodine) with the mechanistic explanation. In sequence, to investigate the utility of the new scaffold, 2D & 3D similarity screening and chemo-centric molecular target prediction were conducted to propose plausible target profiling. The selected list of predicted target proteins was proved by the experimental assay. As another example, asymmetric catalyzed dearomatization will be added with closed information.
====================================== 제 목 : Tailor-made Synthesis of Multilayered Trimetallocyclophanes via Transannula p-p Interactions 연 사 : 정옥상 교수님(부산대학교 화학과) 일 시 : 2018년 4월 5일(목) 오후 4시 15분 장 소 : 화학관 1층 첨단강의실(330118호) -------------------------------------- Tailor-made Synthesis of Multilayered Trimetallocyclophanes via Transannula p-pInteractions Ok-Sang Jung* Department of Chemistry, Pusan National University, Pusan 609-735, Korea Abstract Synthesis and operation of a nano-demension 24 × 24 × 15 Å3 “left and right ball-joint-type host-guest system” via one π∙∙∙π interaction and three NH∙∙∙O=C hydrogen-bonds along with the combined helicity are described. The system consists of unprecedented conglomerate aggregates of two distinct helical metallacyclophanes, chiral isomer (P)-[Pd3X6(L1)2]@(M)- [Pd3X6(L1)(L2)] and its enantiomer (M)-[Pd3X6(L1)2]@(P)- [Pd3X6(L1)(L2)]are described. Successive reactions afford desirable four-layered metallacyclophanes via tailor-made procedure. Synthesis and operation of a nano-demension size multilayered metallacyclophane system via one π∙∙∙π interaction along with the combined helicity are described. A synthetic strategy of generation of new molecular species utilizing a provision of nature has been reported: nano-dimensional (23(2) × 21(1) × 16(1) Å3) hetero four-layered trimetalla- cyclophanes via the proof-of-concept experiments that utilize a suitable combination of π∙∙∙π interactions between the central aromatic rings, tailor-made short/long spacer tridentate donors, and the combined helicity are constructed. The unprecedented four-layered metallacyclophane system’s behavior offers a landmark in the development of new molecular system.
============================================================== 제 목 : Transition-Metal-Catalyzed Coupling ReactionsDecarboxylative Coupling & High Throughput Screening Methods 연 사 : 이선우 교수님(전남대학교) 일 시 : 2018년 3월 15일(목) 오후 4시 30분 장 소 : 화학관 2층 세미나실(330226호실) ============================================================== Transition-Metal-Catalyzed Coupling Reactions Decarboxylative Coupling & High Throughput Screening Methods Sunwoo Lee* Department of Chemistry, Chonnam National University, Gwangju 61186 Republic of Korea Transition-metal-catalyzed decarboxylative coupling of alkynoic acids have been studied by our lab for a decade. Since our first report that palladium-catalyzed reactions of aryl halides and propiolic acids afforded the symmetrical and unsymmetrical diaryl alkynes in good yields, a variety of related methodology have been reported by many research groups including us. The development of simple and convenient method for the preparation of aryl alkynoic acids made it easy accessible tool for the introduction of alkynyl group in organic synthesis. Although the decarboxylative coupling of alkynoic acids and Sonogahsira type coupling of terminal alkyne showed similar reactivity in most cases, the unique reactivity of alkynoic acid has been found in the multicomponent reactions including metal-free reactions. Especailly, arylpropiolic acids readily prepared from the coupling reaction of aryl halides and propiolic acid without column chromatography procedure. In this presentation, we would like to discuss some of our recent research progress towards the decarboxylative coupling reactions of alkynoic acids. The development of efficient reaction conditions often requires many rounds of screening. This can be especially true in the case of metal-catalysed couplings, such as the always-popular palladium-catalyzed cross couplings, where it may be necessary to investigate the metal source, ligand, solvent, reaction temperature and bases as well as other additives. Because of the demand for the fast analysis of reaction leads to synthetic methodology development, we developed colorimetric analysis methods using gold nanoparticles, chemosensor and paper based colorimetric iodide sensor (PBCIS). In this seminar, the recent developed decarboxylative coupling reactions and high throughput screening protocol will be presented.
============================================================== 제 목 : Photosynthesis of Value-added Chemicals from Carbon Dioxide and Water Using Oxide Semiconductors 연 사 : 박현웅 교수님(경북대학교) 일 시 : 2017년 12월 14일(목) 오후 4시 30분 장 소 : 화학관 1층 대강의실 (330102호실) ============================================================== Photosynthesis of Value-added Chemicals from Carbon Dioxide and Water Using Oxide Semiconductors Hyunwoong ParkSchool of Energy Engineering, Kyungpook National University, Daegu 41566, Korea E-mail: hwp@knu.ac.kr As the costs of carbon-footprinted fuels change continuously and atmospheric carbon dioxideconcentration increases, solar fuels are receiving growing attention as alternative cleanenergy carriers. These fuels include molecular hydrogen and hydrogen peroxide producedfrom water, and hydrocarbons converted from carbon dioxide. For high efficiency solar fuelproduction, not only light absorbers (oxide semiconductors, Si, inorganic complexes, etc)should absorb most sunlight, but also charge separation and interfacial charge transfers needto occur efficiently. Recently, there is renewed interest in the photocatalytic andphotoelectrochemical conversion of CO2 into value-added chemicals using varioussemiconductor particles and electrodes. Common CO2 reduction products are C1 chemicals(CO, HCOOH, CH3OH, and CH4) in aqueous media, while the production of C2-C4hydrocarbons (e.g., C2H6 and C3H8) has also been reported. A number of solar-activematerials have been reported, but they still suffer from low selectivity, poor energy efficiency,and instability, while failing to drive simultaneous water oxidation. This talk presents ourrecent studies on the solar CO2 conversion to value-added chemicals while using water as anelectron donor in various photo-systems.
====================================== 제 목 : Multiple routes of light signaling to the roots - Photochemical approaches - 연 사 : 박충모 교수님(서울대학교) 일 시 : 2017년 11월 30일(목) 오후 4시 15분 장 소 : 화학관 1층 대강의실(330102호) -------------------------------------- Multiple routes of light signaling to the roots - Photochemical approaches - Chung-Mo Park Department of Chemistry, Seoul National University Tel: 02-880-6640, e-mail: cmpark@snu.ac.kr Living organisms sustain their growth and performance through intricate communications with surrounding environments under changing climates. Accumulating evidence support that the living organisms-environment communication occurs via a wide variety of chemicals, which are often termed chemical language. Light is one of the most important communication media that affect plant growth and development by influencing virtually all aspects of plant growth and developmental processes throughout plant life. A group of photoreceptors perceives a wide range of light wavelengths, such as ultra-violet (UV), blue (B), red (R), and far-red (FR), to monitor the plant’s surrounding environment. The roles of photoreceptors and associated signaling mechanisms have been extensively investigated mostly in the photomorphogenic processes of aerial plant parts. Notably, recent studies strongly support that light also influences the underground root system. However, how the aboveground light influences the root system has not been explored. Here, we show that light is efficiently piped through the stems to the roots, where photoactivated phytochrome B (phyB) triggers photomorphogenic responses, such as root growth and gravitropism. These findings demonstrate that the underground roots directly sense stem-piped light to monitor the aboveground environment during environmental adaptation. Our data would also provide molecular insights into plant intellectual behaviors and, in particular, clues as to a long-sought hypothesis ‘Do plant roots harbor brain or brain-like tissues?’ proposed by Charles Darwin.
============================================================== 제 목 : Construction of Quaternary Stereocenters via Pd-Catalyzed Asymmetric Decarboxylative Cycloaddition 연 사 : Prof. Yong Jian Zhang 일 시 : 2017년 11월 23일(목) 오전 10시 30분 장 소 : 화학관 2층 서병인강의실 (330226호실) ============================================================== Construction of Quaternary Stereocenters via Pd-Catalyzed Asymmetric Decarboxylative Cycloaddition Yong Jian Zhang School of Chemistry and Chemical Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, China yjian@sjtu.edu.cn The development of efficient methods for the construction of quaternary stereogenic centers is an important objective in modern organic synthesis. In this presentation, I will present our recent research results for the construction of quaternary stereogenic centers via palladium-catalyzed asymmetric decarboxylative cycloaddition of vinylethylene carbonates (VECs) with unsaturated electrophiles. By using chiral palladium complex as catalysts under mild conditions, the transformations that enable rapid access valuable functional heterocycles bearing quaternary stereocenters in high yields and high levels of stereoselectivities.
============================================================== 제 목 : C−H Activation Using Organophosphorus Compounds 연 사 : 이필호 교수님(강원대학교 화학과) 일 시 : 2017년 11월 16일(목) 오후 4시 30분 장 소 : 화학관 2층 서병인강의실 (330226호실) ============================================================== C−H Activation Using Organophosphorus Compounds Phil Ho Lee Department of Chemistry, Kangwon National University C−H bond functionalizations catalyzed by transition metals are interesting since these procedures permit for a more clear-cut synthetic strategy to products devoid of demanding prefunctionalization of starting materials, thus avoiding byproducts in step-economical manner. In order to have a broad synthetic strategy in a C−H functionalization, the desired C−H bond in the starting material should be selectively activated over all the C‒H bonds existing in the substrate. In particular, since there is a trivial difference in the reactivity between the C−H bonds in aromatic compounds, a selective C‒H bond functionalization is very crucial. Recently, a series of examples of C−C and C−heteroatom bond formation have been described by introducing directing groups. As a consequcnce, a number of coordinating directing groups have been employed for atom- and step-economical C−H bond functionalization. Among those, imines, amides and heterocyclic compounds bearing nitrogen are most frequently utilized as directing groups. In addition, C−H functionalization using hydroxyl and carboxyl as directing groups through weak coordination has been studied to a great extent. However, there is still a need to develop useful functional groups for direct ortho-selective C−H bond cleavage, which will provide a significant effect in synthetic applications. Encouraged by a number of transition metal-catalyzed cyclizations using a carboxylic acid group, we imagined that C−H bond functionalization with phosphonic acid monoesters would perform as a desirable platform for the preparation of phosphaisocoumarins, which may be phosphorus heterocycles exhibiting effective biological activity. Moreover, to date, phosphaisocoumarin scaffolds have been synthesized through intramolecular cyclization. Although alkynylarylphosphates or their monoesters have been used in the cyclization, as far as we know, Rh-catalyzed cyclization using alkynes and arylphosphonic acid monoesters has not been utilized for the synthesis of phosphaisocoumarins. Furthermore, to the best of our knowledge, methods using phosphorus compound as a directing group is few. Inspired by recent our interests in organophosphorus compounds, we decided to examine C−H bond functionalization with phosphonic acid monoester. Rh-catalyzed cyclization of phosphinic acids and phosphonic monoesters with alkynes has been developed. The oxidative annulations proceeds with complete conversion of phosphinic acid derivatives and allowed the atom-economic preparation of useful phosphaisocoumarins with high yield and selectivity. The reaction is tolerant of extensive substitution on the phosphinic acid, phosphonic monoester and alkyne, including halides, ketone, and hydroxyl groups as substituents. Furthermore, we found that alkenylphosphonic monoesters proceed to give a wide range of phosphorus 2-pyrones through oxidative annulations with alkynes. Mechanistic studies revealed that C−H bond metalation was the rate-limiting step. An efficient and cost-effective Ru-catalyzed oxidative cyclization of phosphonic acid monoesters or phosphinic acids with alkynes has been developed for the synthesis of a wide range of phosphaisocoumarins in good to excellent yields under aerobic conditions. A multitude of arylphosphonic acid monoesters and arylphosphinic acids having electron-donating and -withdrawing groups were oxidatively cyclized. Various diarylacetylenes, dialkylacetylenes, and alkylarylacetylenes effectively underwent Ru-catalyzed oxidative cyclization. A substrate possessing benzoic acid as well as a phenylphosphonic monoester moiety was smoothly cyclized with hex-3-yne to afford a compound having both isocoumarin and phosphaisocoumarin moieties. Alkenylphosphonic monoester afforded phosphorus 2-pyrone through oxidative cyclization with alkyne. Competition experiments between diaryl- and dialkylalkynes and between diarylacetylenes having 4-methoxy and 4-chloro groups gave results which showed that the present oxidative cyclizations were not affected by the electronic effects of alkynes. Mechanistic studies revealed C−H bond metalation to be the rate-limiting step. References 1. Chan, L. Y.; Kim, S.; Ryu, T.; Lee, P. H. Chem. Commun. 2013, 49, 4682. 2. Chary, B. C.; Kim, S.; Park, Y.; Kim, J.; Lee, P. H. Org. Lett. 2013, 15, 2692. 3. Seo, J.; Park, Y.; Jeon, I.; Ryu, T.; Park, S.; Lee, P. H. Org. Lett. 2013, 15, 3358. 4. Ryu, T.; Kim, J.; Park, Y.; Kim, S.; Lee, P. H. Org. Lett. 2013, 15, 3986. 5. Park, S.; Seo, B.; Shin, S.; Son, J.-Y.; Lee, P. H. Chem. Commun. 2013,49, 8671. 6. Mo, J.; Lim, S.; Park, S.; Ryu, T.; Kim, S.; Lee, P. H. RSC Adv. 2013, 3, 18296. 7. Park, Y.; Seo, J.; Park, S.; Yoo, E. J.; Lee, P. H. Chem. Eur. J. 2013,19, 16461. 8. Kim, C.-E.; Ryu, T.; Kim, S.; Lee, K.; Lee, C.-H.; Lee, P. H. Adv. Synth. Catal. 2013, 355, 2873. 9. Kang, D.; Cho, J.; Lee, P. H. Chem. Commun.2013, 49, 10501. 10. Park, Y.; Jeon, I.; Shin, S.; Min, J.; Lee, P. H. J.Org. Chem. 2013, 78, 10209. 11. Eom, D.; Jeong, Y.; Kim, Y. R.; Lee, E.; Choi, W.; Lee, P. H. Org. Lett. 2013,15, 5210. 12. Kim, J.; Kang, D.; Yoo, E. J.; Lee, P. H. Eur. J. Org. Chem. 2013, 7902. 13. S. Shin, D. Kang, W. H. Jeon, P. H. Lee, Beilstein J. Org. Chem. 2014, 10, 1220 (invited). 14. Shin, S.; Jeong, Y.; Jeon, W. H.; Lee, P. H. Org. Lett. 2014, 16, 2930. 15. Kim, Y. R.; Cho, S.; Lee, P. H. Org. Lett.2014, 16, 3098. 16. Kim, C.-E.; Son, J.- Y.; Shin, S.; Seo, B.; Lee, P. H. Org. Lett. 2015, 17, 908. 17. Jeon, W. H.; Son, J.-Y.; Kim, S.-E.; Lee, P. H.Adv. Synth. Catal. 2015, 357, 811. 18. Son, J.-Y.; Kim, H.; Jeon, W. H.; Baek, Y.; Seo, B.; Um, K.; Lee, K.; Lee, P. H. Adv. Synth. Catal. 2017, 359, 3194.
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