Synthesis of Polymer-Supperted Organotinhydride Reagents and Their Use in Cyclization Reactions

DergiPark: 242143trakyafbdBu çalışmanın amacı geniş bir kullanım alanı olan kalay hidrürlerin reaksiyon sonrası saflaştırma problemlerini minimuma indirgemek için bir poliınere bağlayarak kullanmaktır. İlk olarak MA 280 000 olan lineer polistiren ile çalışılmış, bu polimere önce brom bağlanmış, ardından bu bromun farklı alkil grupları ile yer değiştirilmesi denenmiştir. Lineer polimerin n-BuLi ile kullanılınası sorun olduğundan kullanımından vazgeçilmiştir. Toz halindeki çapraz bağlı polimerlerden de aynı nedenle vazgeçilerek ticari olarak satılan XAD4 tipi boncuk 20-50 mesh büyüklüğündeki polimerler ile çalışmalar yapılmıştır. Amacımıza uygun çapraz bağlı polimerler süspansiyon polimerleşmesi ile de elde edilerek kullanılmıştır. Yapılan deneylerde çok değişik boyutlarda ve çapraz bağlı yapıya sahip polimerler elde edilmiş ama bu polimerler ile de yapılan çalışmalarda poliıner destekli kalay hidrür bileşiği oluşmamıştır. Amacımızı gerçekleştirmek için çalışmalarda monomerlerden başlanılmasına karar verilmiş, bunun için ilk olarak DVB ile Bu2SnHCl reaksiyona sokularak, sonraki aşamada polimerleşme gerçekleştirilmiştir. Bu polimerleşme; süspansiyonal, çözelti polimerleşmesi ve kütle polimerleşmesi olarak da yapılmıştır. Bunlardan süspansiyonal polimerleşmeden sonuç alınamadığı için vazgeçilmiş, diğer iki çalışmadan ise istenilen sonuç alınmıştır. Elde edilen polimer hem LiAlH4 hemde DIBAL-H ile indirgenmiş, LiALH4 ile daha iyi sonuç alınmıştır. Amaçlanan polimer elde edilince aktifliğini incelemek için oktil bromür ile reaksiyona sokulmuş ve oktil bromürün indirgendiği gaz kromatografısi, TLC ve JR spektrumu ile ispatlanmıştır.The purpose of this study is to prepare polymer-supported organotin hydrides, which have a wide range of use, so that, purification problems may be eliminated. First of all, lınear polystyrene (MA 280 000) was used in our studies. Initially, bromine was attached, followed by some different alkyl groups. We stopped working with this polymer due to problematic use of n-BuLi, and then it was done with the powdered cross-linked resins for the same reason. Instead, commercially available XAD4 bead resin (20-50 mesh), which can easily be swollen in appropriate solvents, became the one worked with. We tried to synthesize the desired resin, which was appropriate for our purpose, by suspension polymerization with different degree of cross-linking and with different mesh size. We classified synthesized resins using different size of the sieves and worked with these resins. The studies that have been done with these resins have also not helped us to get the polymer-supported organotin compounds. As a result, tin compound was connected to monomer by reacting DVB with Bu2SnHCI, followed by the polymerization which has been performed via suspension polymerization, solution polymerization, and bulk polymerization. Suspension polymerization was dropped because it didn't give expected results. Yet, other two studies that have been done via solution and bulk polymerization did give expected results. Obtained resins were reduced both with LiAIH4 and with DIBAL-H. The results obtained from the reduction reactions with LiAlH4 were more satisfactory. After synthesizing the desired reagent, we test the activity by using 1-bromooctane and monitored the reaction with TLC, GC and IR proofing the reduction of 1-bromooctane to octan

DSC STUDIES ON MELT CRYSTALLIZED, DRAWN AND FUMING NITRIC-ACID OXIDIZED POLYETHYLENE

Melting, recrystallisation and remelting of undrawn and drawn linear polyethylene with different molecular weight were studied by differential scanning calorimetry before and after oxidation with nitric acid.Publisher's Versio

Synthesis, structural aspects, antimicrobial activity and ion transportation investigation of four new [2+2] condensed 24-membered cycloheterphane peptides

Dulger, Basaran/0000-0002-3184-2652; Zaim, Omer/0000-0002-3472-5611; Dulger, Basaran/0000-0002-3184-2652WOS: 000339274100016Four novel [2 + 2] condensed tetramide-tetrathioether cycloheterophane (L (1) -L (4) ), possessing thioether as ligating units have been prepared. The compounds were characterized by elemental analyses, mass, FT-IR, H-1, and C-13 NMR spectral data. The 24-membered macrocycles have well organized symmetrical structures lacking any configurational isomerism. Ion transportation was carried out with macrocycle L (1) and L (4) against Na+, K+ and Ag+ cations. It showed a high propensity of binding with soft Ag+ cation that it undergoes configurational change during complexation. This phenomenon is not observed with hard cations, but K+ ion passes through the cavity while Na+ ions are retained. The antimicrobial activities of the compounds were evaluated using the disk diffusion method in dimethyl sulfoxide as well as the minimal inhibitory concentration dilution method, against several bacteria and yeast cultures. The results were compared with those of commercial antibiotic and antifungal agents. Structure activity relationships were also discussed.Fatih University Scientific Research CentreFatih University [P50021202_Y(2363)]; Trakya UniversityTrakya University [TUBAP-2010/174]We would like to extend our gratitude to the Fatih University Scientific Research Centre (Project-P50021202_Y(2363) and the Trakya University (Grant # TUBAP-2010/174) for their financial support. Dr. Ahmet Ceyhan Goren and Gokhan Bilsel (TUBITAK-UME), is acknowledged for the Mass analysis

Synthesis, structural aspects, antimicrobial activity and ion transport investigation of five new [1+1] condensed cycloheterophane peptides

Zaim, Omer/0000-0002-3472-5611; Dulger, Basaran/0000-0002-3184-2652; Dulger, Basaran/0000-0002-3184-2652; Gurbuz, Mustafa Ulvi/0000-0002-8684-5746WOS: 000334496700015Five novel [1+1] condensed cycloheterophane peptides were synthesized via reaction of pyridine-2,6-bis(2-aminothiophenoxymethyl) with several diacid chlorides: glutaryl dichloride, adipoyl dichloride, 2,2'-thiodiacetyl chloride, dithiodiglycoloyl chloride and 3,3'-thiodipropionoyl chloride combinations (L-1-L-5). The compounds were characterized by elemental analyses, mass, FT-IR, H-1, and C-13 NMR spectral data. The antimicrobial activities of the compounds were evaluated using the disk diffusion method in dimethyl sulfoxide as well as the minimal inhibitory concentration dilution method, against several bacteria and yeast cultures. The results were compared with those of commercial antibiotic and antifungal agents. Structure activity relationships were also discussed. Permeability of compound L-5 against Na+ and K+ were also investigated.Fatih University Scientific Research CentreFatih University [P50021004_G1452]; Trakya UniversityTrakya University [TUBAP-2010/174]We would like to extend our gratitude to the Fatih University Scientific Research Centre ( Project-P50021004_G1452) and the Trakya University (Grant # TUBAP-2010/174) for their financial support. Dr. Ahmet Ceyhan Goren and Gokhan Bilsel (TUBITAK-UME), is acknowledged for the Mass analysis

An ANP and fuzzy TOPSIS-based SWOT analysis for Turkey's energy planning

Energy planning involves a perpetual process of reevaluating alternative energy strategies. Authorities responsible for energy planning and management have to adjust their strategies according to new and improved alternative solutions based on the sustainability criteria. In this study, we propose an integrated hybrid methodology for the analysis of Turkey’s energy sector using Strengths, Weaknesses, Opportunities, and Threats (SWOT) analysis, Analytic Network Process (ANP) process, and weighted fuzzy Technique for Order Performance by Similarity to Ideal Solution (TOPSIS) to formulate and holistically analyze the energy strategy alternatives and priorities. The methodology proposed in this study allowed identifying the relevant criteria and sub-criteria using a SWOT analysis. Then, ANP approach, which is one of the popular multi-criteria decision making (MCDM) methods, is employed to determine the weights of each SWOT factors and sub-factors. Finally, fuzzy TOPSIS methodology is conducted to prioritize alternative energy strategies. We discuss the obtained results for the development of long-range alternative energy strategies. The results showed that turning the country into an energy hub and an energy terminal by effectively using the geo-strategic position within the framework of the regional cooperation is the most important priority. On the other hand, using the nuclear energy technologies within the energy supply strategies found to be the least favored priority.Q1WOS:0004170794001102-s2.0-8502835552

Using machine learning tools for forecasting natural gas consumption in the province of Istanbul

Commensurate with unprecedented increases in energy demand, awell-constructed forecastingmodel is vital to managing energy policies effectively by providing energy diversity and energy requirements that adapt to the dynamic structure of the country. In this study, we employ three alternative popular machine learning tools for rigorous projection of natural gas consumption in the province of Istanbul, Turkey's largest natural gas-consuming mega-city. These tools include multiple linear regression (MLR), an artificial neural network approach (ANN) and support vector regression (SVR). The results indicate that the SVR is much superior to ANN technique, providing more reliable and accurate results in terms of lower prediction errors for time series forecasting of natural gas consumption. This study could well serve a useful benchmarking study for many emerging countries due to the data structure, consumption frequency, and consumption behavior of consumers in various time-periods.Q1WOS:0004746811000682-s2.0-8506311490