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"Sintesis Tris(4-Metoksifenil)Fenilsilan Menggunakan Fenilsilan dan 4-Iodida Anisol dengan Katalis Senyawa Kompleks Paladium. Sintesis tris(4-metoksifenil)fenilsilan melalui reaksi kopling antara fenilsilan dan 4-iodida anisol menggunakan senyawa paladium tersier tributilfosfin sebagai katalis telah dilakukan berdasarkan penentuan senyawa basa, pelarut, dan waktu reaksi kopling. Hasil penelitian menunjukkan bahwa senyawa tris(4-metoksifenil)fenilsilan dapat disintesis menghasilkan persentase produk maksimum pada penggunaan senyawa 1,4-diazabisiko[2,2,2]oktan (DABCO) sebagai basa, tetrahidrofuran sebagai pelarut, dan waktu reaksi kopling selama 5 hari. Persentase tertinggi produk senyawa tris(4-metoksifenil)fenilsilan adalah 35%.

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The synthesis of tris(4-methoxyphenyl)phenylsilan through the coupling reaction of phenylsilane and 4-iodoanisole using palladium tertiary tributylphosphine as a catalyst was carried out through the determination of the base, solvent, and reaction time. The results showed that tris(4-methoxyphenyl)phenylsilane can be synthesized to form maximum yield using 1,4-diazabicyclo[2,2,2]octane (DABCO) as a base, tetrahydrofuran as a solvent, and a 5-day reaction time. The highest yield of tris(4-methoxyphenyl)phenylsilane was 35%."

"The author has developed novel methodologies for highly efficient construction of functionalized heterocycles by palladium-catalyzed domino/cascade cyclization of allenes and related compounds containing appropriate nucleophilic group(s). Based on these methodologies, enantioselective total syntheses of bioactive natural products, pachastrissamine (26% overall yield in seven steps), lysergic acid (4.0% overall yield in fifteen steps), lysergol (3.6% overall yield in fifteen steps) and isolysergol (8.2% overall yield in eleven steps) have been achieved. "

"This book about selectivity in palladium catalyzed allylic substitution, computational insights into palladium-mediated allylic substitution reactions, palladium-catalyzed enantioselective allylic substitution, iridium-catalyzed asymmetric allylic substitutions, molybdenum- and tungsten-catalyzed enantioselective allylic substitutions, copper-catalyzed enantioselective allylic substitution, allylic substitutions catalyzed by miscellaneous metals, and enantioselective allylic substitutions in natural product synthesis."

"Fenomena transfer spin pada sistem lapisan magnetik dapat dipahami sebagai interaksi antara normal metal dengan lapisan feromagnetik terdekatnya yang dipengaruhi oleh suseptibilitas magnetik normal metal. Sebagian besar kajian eksperimen terhadap fenomena transfer spin menggunakan logam berat seperti Paladium dan Platina yang memiliki interaksi Coulomb yang cukup besar, sementara itu teori yang ada saat ini mengasumsikan memakai logam ringan, yang mengabaikan interaksi Coulomb tersebut. Pada penelitian ini, kami bertujuan untuk mempelajari secara teoretis pengaruh dari interaksi Coulomb terhadap suseptibilitas magnetik kompleks. Kami memakai model satu pita energi dengan menggunakan perhitungan Density Functional Theory (DFT), model Hubbard dan model Tight-binding. Hasil perhitungan menunjukkan bahwa untuk logam berat, sifat material didominasi oleh orbital-d, dan suseptibilitas magnetik kompleks mengalami penguatan akibat adanya interaksi Coulomb. Pada logam transisi seperti Pd dan Pt, kulit terluar memiliki orbital-orbital d dan orbital s yang dapat berinteraksi. Kami melakukan kalkulasi pendekatan dua pita energi dengan menggunakan model Anderson, Density Functional Theory, interpolasi Wannier, dan intepolasi pita energi. Dari hasil DFT kami mengamati adanya hibridisasi orbital-s dengan orbital-d. Hasil perhitungan teoretis menujukkan bahwa untuk elektron pita konduksi dari orbital-s, besaran Stoner proporsional terhadap kuadrat dari parameter hibridisasi serta berkebalikan dengan kuadrat dari selisih energi elektron orbital-s terhadap energi dari elektron orbital-d. Hasil perhitungan juga menujukkan bahwa untuk sistem fermion berat, nilai suseptibilitas magnetik ditentukan oleh nilai massa efektif elektron. Hasil perhitungan kami menunjukkan bahwa model dua pita energi mampu memodelkan suseptibilitas magnetik dengan akurat.

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Spin transfer torque in a magnetic multilayer system can be viewed as interaction between a normal metal and adjacent ferromagnetic layer. The magnetic susceptibility of normal metal plays essential role in characterizes the interaction. Most experimental studies on this subject utilize heavy metals, such as Palladium (Pd) and Platinum (Pt), that possess large Coulomb interaction, while a recent theory assume a light metal as normal metal, which neglect the Coulomb interaction. In this research, we aim to theoretically investigate the effect of Coulomb interaction to the complex magnetic susceptibility of Pd and Pt. We calculate a single-band susceptibility for Pd and Pt by applying Density Functional Theory (DFT), tight-binding model, and Hubbard model. For single-band susceptibility,  our final results show that the d-orbitals dominate the band structure with large repulsive interaction that enhances the magnetic susceptibility. To extend our study, we calculate the more complex approaches. Transition metals Pd and Pt outer shell d-orbitals and s-orbital can interact. We calculate the double-band model using the Aderson model, Density Functional Theory, Wannier interpolation, and band fitting. From the DFT calculation, we observe s-d hybridization for Pd and Pt. Our theoretical results show that for conduction electron, the Stoner term is proportional to the square of the hybridization parameter and the inverse of the square of the energy difference between the s and d-electron. We also obtain that for the heavy fermionic system, the magnetic susceptibility value strongly determined by the effective mass of the electron. Our results show that dual-band model is sufficient to model the magnetic susceptibility accurately. "

"Suatu metode sintesis yang unik telah digunakan dalam membuat senyawa turunan 2-(4-metoksifenil)-4-fenil-1,10-fenantrolin (5) dari 4-metoksibenzaldehida (1), asetofenon (2), dan 8-aminokuinolin (4)dengan reaksi kondensasi aldol dan reaksi siklisasi. Turunan-turunan senyawa tersebut diuji aktivitasnya melalui uji aktivitas antiplasmodial. Sintesis turunan senyawa 5 dilakukan dalam tiga tahap. Senyawa 3-(4-metoksifenil)-1-fenilpropenon3 disintesis melalui reaksi kondensasi aldol dari senyawa1 dan 2 dengan hasil 96,42%. Senyawa 5 disintesis melalui siklisasi senyawa 4 dan 3 dengan hasil 84,55%. Turunan senyawa 5 disintesis dari senyawa 5 menggunakan DMS dan DES yang direfluksberturut-turut selama 21 dan 22 jam untuk menghasilkan (1)-N-metil-9-(4-metoksifenil)-7-fenil-1,10-fenantrolinium sulfat (6) dan (1)-N-etil-9-(4-metoksifenil)-7-fenil-1,10-fenantrolinium sulfat (7) dengan rendemen hasil berturut-turut 91,42 dan 86,36%. Hasil uji in vitro aktivitas antiplasmodium dari turunan senyawa 5 (senyawa 6 dan 7) terhadap P.falciparum resistan klorokuin strain FCR3 menunjukkan bahwa senyawa 7 mempunyai aktivitas antimalaria lebih tinggi dari senyawa 5 and 6. Sedangkan, hasil uji in vitro aktivitas antiplasmodium terhadap P. falciparum sensitif klorokuinstrain D10 menunjukkan bahwa senyawa6 mempunyai aktivitas antimalaria lebih tinggi dari senyawa 5 and 7.

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AbstractA unique of synthetic methods was employed to prepare 2-(4 methoxyphenyl)-4-phenyl-1,10-phenanthroline (5) derivatives from 4-methoxy-benzaldehyde (1), acetophenone (2), and 8-aminoquinoline (4)with aldol condensation and cyclization reactions. The derivatives were tested through antiplasmodial test. The synthesis of derivatives compound 5 was conducted in three steps. The 3-(4-methoxyphenyl)-1 penylpropenone 3 was synthesized through aldol condensation of 1 and 2 which has a yield of 96.42%. The compound 5 was synthesized through cyclization of compound 4 and 3 with 84.55% yield. The derivative of compound 5 was synthesized from compound 5 using DMS and DES reagents which refluxed for 21 and 22 h, to produce (1)-N-methyl-9-(4-methoxyphenyl)-7-phenyl-1,10-phenanthrolinium sulfate (6) and (1)-N-ethyl-9-(4-methoxyphenyl)-7-phenyl-1,10-phenanthrolinium sulfate (7) with 91.42 and 86.36% yields, respectively.Results of in vitrotesting of antiplasmodial activity of compound 5 derivatives(i.e., compound 6 and 7 ) against chloroquine-resistantP. falciparumFCR3 strain showed that compound 7had higherantimalarial activity than compounds 5 and 6 .Whereas, results of in vitrotesting against chloroquine-sensitive P.falciparumD10 strain showed that compound 6has higher antimalarial activity than compounds 5 and 7. "

"Despite very active research activities in the field of CMA, there lacks a simple-to-read book for researchers and students interested in these new developments. In each chapter, current progress in the area of the synthesis, characterization, and self-assemblies of well-defined complex macromolecular architectures is reviewed by each contributor with relevant emphasis on their research topics. The architectural polymers include bio-conjugated hybrid polymers with poly(-amino acid)s and gluco-polymers, star-branched and dendrimer-like hyperbranched polymers, cyclic polymers, dendrigraft polymers, rod-coil and helix-coil block copolymers are introduced chapter by chapter in the book. In particular, the book also emphasizes the topic of synthetic breakthroughs by living/​controlled polymerization since 2000. Newly developed concepts and procedures, such as "Click" chemistry, chain walking, polyhomologation and ADMET are also highlighted. Furthermore, renowned authors contribute on such special topics as helical polyisocyanates, metallopolymers, stereospecific polymers, hydrogen-bonded supramolecular polymers, conjugated polymers, and polyrotaxanes, which have attracted considerable interest as novel polymer materials with potential future applications. In addition, recent advances in reactive blending achieved with well-defined end-functionalized polymers is discussed from an industrial point of view. Moreover, topics on polymer-based nanotechnologies, including self-assembled architectures and suprastructures, nano-structured materials and devices, nanofabrication, surface nanostructures, and their AFM imaging analysis of hetero-phased polymers are included"--"In particular, the book also emphasizes the topic of synthetic breakthroughs by living/​controlled polymerization since 2000"

"Pada penelitian ini dilakukan sintesis ester asam oleat-BHA dan asam oleat-BHT dengan menggunakan reaksi esterifikasi Steglich. Produk yang terbentuk dilakukan pemurnian dengan menggunakan kromatografi kolom. Hasil karakterisasi FTIR asam oleat-BHA menunjukkan serapan dengan munculnya puncak serapan baru yang khas pada ester yaitu C=O pada bilangan gelombang 1738,9 cm-1 dan serapan gugus aromatis pada bilangan gelombang 1442 dan 1457 cm-1. Terbentuknya asam oleat-BHT dibuktikan dengan adanya puncak serapan C=O ester pada bilangan gelombang 1742,2 cm-1 dan puncak serapan gugus aromatis pada bilangan gelombang 1435 dan 1458,9 cm-1. Hasil karakterisasi UV menunjukkan adanya pergeseran hipsokromik produk terhadap BHA dan BHT dan batokromik terhadap asam oleat. Hasil uji toksisitas asam oleat-BHA dan asam oleat-BHT terhadap larva Artemia salina L menunjukkan bahwa ester hasil sintesis tidak toksik yaitu dengan nilai LC50 yaitu 3370,91 (asam oleat-BHA) dan 1209,18 ppm (asam oleat-BHT). Nilai IC50 asam oleat-BHA yaitu 22,61 ppm menunjukkan aktivitas antioksidan yang tinggi dan asam oleat-BHT sebesar 136,42 ppm menunjukkan aktivitas antioksidan yang sedang. Uji antibakteri yang dilakukan menunjukkan bahwa asam oleat-BHA memiliki aktivitas yang lemah terhadap bakteri Escherichia coli dan tidak memiliki aktivitas terhadap Staphyloccocus aureus, sedangkan asam oleat-BHT tidak memilki aktivitas terhadap kedua bakteri tersebut.

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In this study, the synthesis of oleic acid-BHA and oleic acid-BHT esters was carried out using the Steglich esterification reaction. The product formed was purified using column chromatography. The results of the FTIR characterization of oleic acid-BHA showed absorption with the appearance of a new absorption peak that was unique to the ester, C=O at a wave number of 1738.9 cm-1 and an absorption peak of an aromatic group at a wave number of 1442 and 1457 cm-1. The formation of oleic acid-BHT was evidenced by the absorption peak of C=O ester at a wave number of 1742.2 cm-1 and an absorption peak of aromatic groups at wave numbers of 1435 and 1458.9 cm-1. The results of UV characterization showed a hypochromic shift of the product towards BHA and BHT and bathochromic to oleic acid. The results of the toxicity test of oleic acid-BHA and oleic acid-BHT on Artemia salina L larvae showed that the ester was non-toxic with LC50 values of 3370.91 ppm (oleic acid-BHA) and 1209.18 ppm (oleic acid-BHT). The IC50 value of oleic acid-BHA which is 22.61 ppm indicated high antioxidant activity and oleic acid-BHT of 136.42 ppm indicated moderate antioxidant activity. The antibacterial test performed showed that oleic acid-BHA had weak activity against Escherichia coli bacteria and no activity against Staphylococcus aureus. While oleic acid-BHT did not have activity against these two bacteria."

"Pada penelitian ini dilakukan sintesis ester asam risinoleat-BHA dan asam risinoleat-BHT melalui reaksi esterifikasi Steglich. Sintesis senyawa ester diawali dengan reaksi kopling menggunakan reagen DCC dan katalis DMAP. Terhadap produk yang diperoleh dilakukan pemurnian dengan kromatografi kolom, sehingga didapatkan produk ester murni. Produk ester dikarakterisasi dengan UV-Vis dan FT-IR. Hasil karakterisasi produk ester dengan FT-IR menunjukkan adanya gugus C=O ester pada bilangan gelombang 1730 cm-1 dan 1731 cm-1 pada masing-masing produk ester-BHA dan ester-BHT. Hasil karakterisasi produk ester dengan UV-Vis memperlihatkan adanya pergeseran batokromik terhadap asam risinoleat dan pergeseran hipsokromik terhadap BHA atau BHT. Produk ester yang diperoleh diuji aktivitas toksisitasnya terhadap larva udang Artemia salina L. dengan metode BSLT. Hasil uji BSLT menunjukkan produk ester asam risinoleat-BHA dan asam risinoleat-BHT memiliki nilai LC50 masing-masing sebesar 258 ppm dan 136 ppm yang menujukkan efek toksisitas yang sedang. Hasil uji antimikroba produk ester asam risinoleat-BHA dan asam risinoleat-BHT terhadap bakteri E. coli dan S. aureus menunjukkan aktivitas antimikroba dengan kekuatan yang lemah.

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In this research, the synthesis of ricinoleic acid-BHA ester and ricinoleic acid-BHT ester through the Steglich esterification reaction. The synthesis of ester compound began with a coupling reaction using DCC reagent and DMAP catalyst. The product obtained was purified by column chromatography, in order to obtain a pure ester product. The ester products were characterized by UV-Vis and FT-IR. The result of the characterization of ester products with FT-IR showed the presence of C=O ester groups at wave numbers 1730 cm-1 and 1731 cm-1 in the ester-BHA and ester-BHT products, respectively. The ester product with UV-Vis showed a shift in the bathochromic character towards ricinoleic acid and a hypsochromic shift towards BHA or BHT. The ester product obtained was tested for toxicity activity against Artemia salina L. shrimp larvae using BSLT method. The result of BSLT test showed the ester products of ricinoleic acid-BHA and ricinoleic acid-BHT have LC50 values ​​of 258 ppm and 136 ppm, respectively, indicating a moderate toxicity effect. The antimicrobial test results for ricinoleic acid-BHA and ricinoleic acid-BHT ester products against E. coli and S. aureus bacteria showed antimicrobial activity with weak strength.

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"Pada penelitian ini dilakukan sintesis ester asam oleat-BHA dan asam oleat-BHT dengan menggunakan reaksi esterifikasi Steglich. Produk yang terbentuk dilakukan pemurnian dengan menggunakan kromatografi kolom. Hasil karakterisasi FTIR asam oleat-BHA menunjukkan serapan dengan munculnya puncak serapan baru yang khas pada ester yaitu C=O pada bilangan gelombang 1738,9 cm-1 dan serapan gugus aromatis pada bilangan gelombang 1442 dan 1457 cm-1. Terbentuknya asam oleat-BHT dibuktikan dengan adanya puncak serapan C=O ester pada bilangan gelombang 1742,2 cm-1 dan puncak serapan gugus aromatis pada bilangan gelombang 1435 dan 1458,9 cm-1. Hasil karakterisasi UV menunjukkan adanya pergeseran hipsokromik produk terhadap BHA dan BHT dan batokromik terhadap asam oleat. Hasil uji toksisitas asam oleat-BHA dan asam oleat-BHT terhadap larva Artemia salina L menunjukkan bahwa ester hasil sintesis tidak toksik yaitu dengan nilai LC50 yaitu 3370,91 (asam oleat-BHA) dan 1209,18 ppm (asam oleat-BHT). Nilai IC50 asam oleat-BHA yaitu 22,61 ppm menunjukkan aktivitas antioksidan yang tinggi dan asam oleat-BHT sebesar 136,42 ppm menunjukkan aktivitas antioksidan yang sedang. Uji antibakteri yang dilakukan menunjukkan bahwa asam oleat-BHA memiliki aktivitas yang lemah terhadap bakteri Escherichia coli dan tidak memiliki aktivitas terhadap Staphyloccocus aureus, sedangkan asam oleat-BHT tidak memilki aktivitas terhadap kedua bakteri tersebut.

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In this study, the synthesis of oleic acid-BHA and oleic acid-BHT esters was carried out using the Steglich esterification reaction. The product formed was purified using column chromatography. The results of the FTIR characterization of oleic acid-BHA showed absorption with the appearance of a new absorption peak that was unique to the ester, C=O at a wave number of 1738.9 cm-1 and an absorption peak of an aromatic group at a wave number of 1442 and 1457 cm-1. The formation of oleic acid-BHT was evidenced by the absorption peak of C=O ester at a wave number of 1742.2 cm-1 and an absorption peak of aromatic groups at wave numbers of 1435 and 1458.9 cm-1. The results of UV characterization showed a hypochromic shift of the product towards BHA and BHT and bathochromic to oleic acid. The results of the toxicity test of oleic acid-BHA and oleic acid-BHT on Artemia salina L larvae showed that the ester was non-toxic with LC50 values of 3370.91 ppm (oleic acid-BHA) and 1209.18 ppm (oleic acid-BHT). The IC50 value of oleic acid-BHA which is 22.61 ppm indicated high antioxidant activity and oleic acid-BHT of 136.42 ppm indicated moderate antioxidant activity. The antibacterial test performed showed that oleic acid-BHA had weak activity against Escherichia coli bacteria and no activity against Staphylococcus aureus. While oleic acid-BHT did not have activity against these two bacteria."

"ABSTRAKPeningkatan konsentrasi CO2 diatmosfer mengakibatkan permasalahan lingkungan sehingga konversi CO2 menjadi bahan kimia dan bahan bakar menarik untuk dikaji. Salah satu alternatif dalam daur ulang siklus karbon terbarukan yaitu dengan reduksi elektrokatalitik CO2 dapat dilakukan dalam kondisi ruang dan mudah dikontrol proses reaksinya dengan pengubahan potensial. Pada penelitian ini, boron-doped diamond dimodifikasi terlebih dahulu dengan AuNP, PdNP dan AuPdNP kemudian diaplikasikan untuk reduksi CO2 secara elektrokimia. Sebelum dilakukan perendaman dengan larutan nanopartikel, BDD dimodifikasi dengan larutan allilamina dibawah sinar UV selama 6 jam. Kemudian direndam dalam larutan koloid nanopartikel. Karakterisasi larutan nanopartikel dilakukan dengan UV-Vis dan TEM, sedangkan BDD termodifikasi dikarakterisasi dengan SEM EDS, XPS dan secara elektrokimia. Elektroreduksi CO2 dilakukan dalam sel dengan dua kompartemen dengan larutan elektrolit NaCl 0,1 M di dalam ruang katoda dan larutan Na2SO4 0,1 M di dalam ruang anoda. Potensial yang digunakan ialah -0,8 V, -0.9V, dan -1,1V vs Ag/AgCl dengan waktu reduksi selama 60 menit. Produk yang dihasilkan dikarakterisasi dengan GC, HPLC dan GC-MS. Efisiensi Faraday tertinggi dihasilkan oleh elektroda BDDN-AuPdNP sebesar 84,564 dan asam asetat sebagai salah satu produk.Kata kunci: Elektroreduksi CO2, nanopartikel emas palladium, boron-doped diamond, modifikasi permukaan.

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ABSTRACTThe increase of CO2 concentrations in atmosphere can cause an environmental problem so CO2 conversion to chemicals and fuels become interesting to be investigated. One of the alternative in recycling renewable carbon cycles is electrocatlytic conversion of CO2 using the electrochemical method due to mild condition and easily controllable in term of reaction process by changing the potential value. In this study, boron doped diamond was previously modified with AuNP, PdNP and AuPdNP then applied for electrochemical reduction. Before modification with nanoparticle solutions, BDD was modified with allylamine under UV light for 6 hours. The nanoparticle solutions were characterized by UV Vis and TEM, while modified BDD was characterized by SEM EDS, XPS and electrochemical characterization. The electroreduction of CO2 was performed on two cell compartments using NaCl 0,1M in cathode and Na2SO4 in anode. The potentials used were 0.8 V, 0.9V, and 1.1V vs. Ag AgCl with a reduction time of 60 min. The resulting products were characterized by GC, HPLC and GC MS. The highest Faradic efficiency is mostly generated by BDDN AuPdNP electrode, approximately 84.564 and the only electrode form these experiments which had produced acetic acid.Keywords the electroreduction of CO2, gold palladium nanoparticle, boron doped diamond, surface modification."