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Öğe 1-(1H-Benzimidazol-1-ylmethyl)-3-[2-(diisopropylamino)ethyl]-1H-benzimidazolium bromide 0.25-hydrate(Int Union Crystallography, 2009) Arslan, Hakan; VanDerveer, Don; Demir, Serpil; Ozdemir, Ismail; Cetinkaya, BekirThe title N-heterocyclic carbene derivative, C23H30N5+center dot Br-center dot 0.25H(2)O, was synthesized using microwave heating and was characterized by H-1 and C-13 NMR spectroscopy and a single-crystal X-ray diffraction study. The structure of the title compound are stabilized by a network of intra-and intermolecular C-H center dot center dot center dot Br hydrogen-bonding interactions. The crystal structure is further stabilized by pi-pi stacking interactions between benzene and imidazole fragment rings of parallel benzo[d] imidazole rings, with a separation of 3.486 (3) angstrom between the centroids of the benzene and imidazole rings. There is also an intermolecular C-H center dot center dot center dot pi interaction in the crystal structure. The C-N bond lengths for the central benzimidazole ring are shorter than the average single C-N bond, thus showing varying degrees of double-bond character and indicating partial electron delocalization within the C-N-C-N-C fragment. The isopropyl group is disordered over two sites with occupancies of 0.792 (10) and 0.208 (10).Öğe 1-(4-tert-Butylbenzyl)-3-(3,4,5-trimethoxybenzyl)benzimidazolium bromide monohydrate(Wiley-Blackwell Publishing, Inc, 2009) Arslan, Hakan; VanDerveer, Don; Demir, Serpil; Ozdemir, Ismail; Cetinkaya, BekirA novel N-heterocyclic carbene derivative, C(28)H(33)N(2)O(3)(+)center dot-Br(-)center dot H(2)O, was synthesized and characterized by elemental analysis, (1)H and (13)C-NMR and IR spectroscopy and a single-crystal X- ray diffraction study. Ions of the title compound are linked by pi center dot center dot center dot pi stacking interactions (face-face separation 3.441 angstrom) and C-H center dot center dot center dot Br and O-H center dot center dot center dot Br interactions. Intra- and intermolecular C-H center dot center dot center dot O interactions are also present. The C-N bond lengths for the compound [1.329 (3), 1.325 (3), 1.389 (3) and 1.391 (3) angstrom] are all shorter than the average single C-N bond length of 1.48 angstrom, thus showing varying degrees of double-bond character.Öğe Bromido[1-(?6-4-tert-butylbenzyl)-3-(2,4,6-trimethylbenzyl)benzimidazol-2-ylidene]chloridoruthenium(II)(Wiley-Blackwell, 2009) Arslan, Hakan; VanDerveer, Don; Ozdemir, Ismail; Demir, Serpil; Cetinkaya, BekirA new ruthenium complex, [RuBrCl(C28H32N2)], has been synthesized and characterized by elemental analysis, H-1 NMR, C-13 NMR, IR-spectroscopy and a single-crystal X-ray diffraction study. The Ru atom in this complex is best described as having a considerably distorted octahedral coordination environment with the arene occupying three coordination sites. Two further coordination sites are occupied by chloride and bromide ligands, while the sixth site is occupied by the carbene. The carbene portion of the ligand is a benzimidazole ring. This ring is connected to the C6H4C(CH3)(3) arene by a CH2 bridge. This leads to a system with very little apparent strain. The two halogen atoms are disordered between Br and Cl. Two partial Cl atoms share the same sites as two partial Br atoms so that the title compound effectively has one Cl and one Br atom. C-H center dot center dot center dot X (X = Cl, Br) hydrogen bonds help to stabilize the crystal structure.Öğe Butylene linked palladium N-heterocyclic carbene complexes: Synthesis and catalytic properties(Elsevier Science Sa, 2011) Demir, Serpil; Ozdemir, Ismail; Arslan, Hakan; VanDerveer, DonNew bis(NHC)-Pd complexes were synthesized and characterized by elemental analysis, H-1 NMR, C-13 NMR, and IR spectroscopy. The reaction of Pd(OAc)(2) and bis(benzimidazolium) salts in DMSO gave the monomeric palladium complex in which the N-heterocyclic carbene was bound to the metal centre. The crystal and molecular structure of the cis-dibromo{1,1'-di[2,3,4,5,6-pentamethylbenzyl]-3,3'-butylene-dibenzimidazol-2,2'-diylidene}-palladium(II) complex was determined by single-crystal X-ray diffraction. The activity of the Pd(II) complexes in the direct arylation of benzothiazole with arylbromides was investigated. A preliminary catalytic study showed that these bis(NHC)-Pd complexes were highly active in the direct arylation of benzothiazole with arylbromides. (C) 2011 Elsevier B.V. All rights reserved.Öğe Carbon monoxide-releasing properties and DFT/TDDFT analysis of [Mn(CO)3(bpy)L]PF6 type novel manganese complexes(Elsevier Science Sa, 2016) Ustun, Elvan; Koc, Sefika; Demir, Serpil; Ozdemir, IsmailNovel manganese(I) carbonyl complexes of the general formula [Mn(CO)(3)(bpy)L]PF6 (bpy = 2,2-bipyridyl, L = N-(2-methylbenzyl)imidazoline, N-(3-methylbenzyl)imidazoline, N-(4-methylbenzyl)imidazoline, N-(2,4,6-trimethylbenzyl)imidazoline) were synthesized and characterized by analytical (LC-MS spectrometry and elemental analysis) and spectroscopic (H-1 NMR, C-13 NMR, cosy2D-NMR, infrared) methods. The CO-releasing properties of these complexes were investigated with myoglobin assay. The DFT/TDDFT calculations were made by ORCA package program with both BP86 and B3LYP functionals. (C) 2016 Elsevier B.V. All rights reserved.Öğe CO-releasing properties and anticancer activities of manganese complexes with imidazole/benzimidazole ligands(Taylor & Francis Ltd, 2016) Ustun, Elvan; Ozgur, Aykut; Coskun, Kubra A.; Demir, Serpil; Ozdemir, Ismail; Tutar, YusufCarbon monoxide (CO) is an important signaling molecule which plays significant roles in the pathogenesis of cancer. CO is produced by enzymatic degradation of heme in mammals. Heme oxygenase 1 (HO-1) catalyzes the breakdown of heme into CO, ferrous iron, and biliverdin. CO induces HO-1 and inhibits cell proliferation. Cancer cells exposed to several stress factors (hypoxia, reactive oxygen species, cis-platin, and oxidative stress), and HO-1 displays cytoprotective role against oxidative stress and inhibits apoptosis, metastases, angiogenesis, and cell proliferation processes. Therefore, metal containing CO-releasing molecules (CORMs) have been designed as an effective cancer treatment strategy. CORMs are responsible for releasing controlled amounts of CO to cells and tissues. Thus, we synthesized [Mn(CO)(3)(bpy)L]X manganese containing CORMs [bpy=2,2-bipyridine, X=hexafluorophosphate (PF6), trifluoromethanesulfonate (OTf), L=imidazole, methylimidazole, benzimidazole, N-benzylbenzimidazole, N-(4-chlorobenzyl)benzimidazole] to release CO in human invasive ductal breast (MCF-7) cell line. In vitro experiments indicated that the compounds inhibited cell proliferation and exhibited cytotoxic effect on breast cancer cells. Moreover, side groups of the compounds enhanced the anticancer effects in MCF-7 cell line. These manganese containing CORMs gave promising results and may be used as a drug template for effective treatment of invasive ductal breast carcinoma. [GRAPHICS] .Öğe The determination of oxidative damage in heart tissue of rats caused by ruthenium(II) and gold(I) N-heterocyclic carbene complexes(Sage Publications Inc, 2011) Ciftci, Osman; Ozdemir, Ilknur; Cakir, Oguz; Demir, SerpilIn the present study, we aimed to determine the oxidative damage in rat heart tissue induced by ruthenium(II)-NHC (Ru) and gold(I)-NHC (Au) complexes which have anticarcinogenic effects and not used clinically yet. For this purpose, 35 Sprague-Dawley ratswere randomly divided into 5 equal groups. In the control group, rats treated with saline, Ru and Au complexes were intraperitoneally given high (10 mg/kg) and low (5 mg/kg) doses as only one administration. The animals were killed, and heart tissues were taken on day 10 of the drug administration for the determination of the biochemical parameters (malondialdehyde, superoxide dismutase, reduced glutathione and catalase levels). It was determined that both Ru and Au complexes treatment significantly caused oxidative damage compared to the control group. Additionally, it was shown that Au treatment causedmore adverse effects than Ru treatment. Also, it was clearly found that the occurred effects were generally determined in a dose-dependent manner. In conclusion, when these compounds synthesized for the treatment of cancer were used, they caused oxidative damage in heart tissue. However, Ru complex could be preferred for cancer treatment in terms of user safety.Öğe Direct arylation of arene C-H bonds by cooperative action of NHCarbene-Ruthenium(II) catalyst and carbonate via proton abstraction mechanism(Amer Chemical Soc, 2008) Ozdemir, Ismail; Demir, Serpil; Cetinkaya, Bekir; Gourlaouen, Christophe; Maseras, Feliu; Bruneau, Christian; Dixneuf, Pierre H.Direct functionalization of sp(2) C-H bonds via ortho diarylation of 2-pyridyl benzene with arylbromides was achieved using ruthenium(II) catalysts containing a RuCl2(NHC) unit and generated from [RuCl2(arene)](2) and two types of NHC precursors, pyrimidinium and benzimidazolium salts, in the presence of Cs2CO3. DFT calculations from RuCl2(NHC)(2-pyridylbenzene) show that a proton abstraction mechanism, on cooperative actions of both the coordinated base and the Ru(II) center, is favoured via a 13.7 kcal mol(-1) exothermic process affording an orthometalated intermediate with a 2.009 angstrom Ru-C bond.Öğe The first used half sandwich ruthenium(II) complexes bearing benzimidazole moiety for N-alkylation of amines with alcohols(Elsevier Science Sa, 2014) Demir, Serpil; Coskun, Feyzullah; Ozdemir, IsmailHalf sandwich ruthenium(II) complexes were synthesized from [RuCl2(eta(6)-p-cymene)](2) and N-substituted benzimidazole. All new compounds were characterized by elemental analysis, H-1 NMR, C-13 NMR, and IR spectroscopy. Aminoarenes were readily converted into secondary amines by the reaction at 150 degrees C with benzyl alcohol and in the presence of a catalytic amount of novel ruthenium complexes. All of [RuCl2(eta(6)-p-cymene)(N-substituted benzimidazole)] complexes were the most effective catalyst for N-alklyation reaction using borrowing hydrogen methodology. (C) 2014 Elsevier B. V. All rights reserved.Öğe Functionalized ionic liquids based on imidazolium cation: Synthesis, characterization and catalytic activity for N-alkylation reaction(Elsevier, 2015) Demir, Serpil; Damarhan, Yunus; Ozdemir, IsmailThe novel functionalized ionic liquids based on imidazolium cation are synthesized and characterized by studying its H-1, C-13, and P-31 NMR and elemental analysis. These ionic liquids have been reported as a highly efficient catalyst for N-alkylation reaction of aniline with butyl chloride. The reaction was efficiently performed in ionic liquid as an environmentally benign solvent with good yields without transition metal. (C) 2015 Elsevier B.V. All rights reserved.Öğe Gold(I) Complexes of N-Heterocyclic Carbene Ligands Containing Benzimidazole: Synthesis and Antimicrobial Activity(Mdpi, 2010) Ozdemir, Ilknur; Temelli, Nazan; Gunal, Selami; Demir, SerpilGold(I) N-heterocyclic carbene (NHC) complexes were obtained in good yields from the corresponding silver complexes by treatment with [AuCl(PPh3)] following the commonly used silver carbene transfer route. The silver complexes were synthesized from the benzimidazolium halide salts by the in situ reactions with Ag2O in dichloromethane as a solvent at room temperature. All gold complexes have been characterized by H-1-NMR, C-13-NMR and IR spectroscopy and elemental analysis. Au-NHC complexes were evaluated for their in vitro antimicrobial activity against a variety of Gram-positive and Gram-negative bacteria and fungal species.Öğe Hacimli benzil grubu içeren diaminokarben komplekslerinin sentezi ve özellikleri(İnönü Üniversitesi, 2001) Demir, SerpilÖZET Yüksek Lisans Tezi HACİMLİ BENZİL GRUBU İÇEREN DİAMİNOKARBEN KOMPLEKSLERİNİN SENTEZİ VE ÖZELLİKLERİ Serpil DEMİR İnönü Üniversitesi Fen Bilimleri Enstitüsü Kimya Anabilim Dalı xi + 74 sayfa 2001 Tez Danışmanı: Yrd.Doç.Dr.İsmail ÖZDEMİR Karben kompleksleri, L"M=CXY, üzerindeki çalışmalar son yıllarda hızlı bir gelişme göstermiştir ve pek çok karben kompleksi sentezlenmiştir. Fakat hacimli ve işlevsel grup içeren JV-heterosiklik karben kompleksleri üzerinde yeterince çalışılmamıştır. Bu çalışmanın amacı, sözkonusu boşluğu doldurmak ve sentezlenen bileşiklerin katalitik özelliklerini incelemektir. Burada üç yeni tetraamindalken (2a-c) ve bunlardan türeyen altı yeni karben kompleksi sentez ve karakterize (3 ve 6 tek kristal X-ışınlan ile) edilmiştir. N üzerinde hacimli benzil (mesitilbenzil) içeren 2a olefini [RuCİ2(p-simen)]2 ve [RuCİ2(HMB)]2 bileşikleriyle etkileştirildiğinde p-simen ve hekzametilbenzen grubu rutenyum metalini terk ederek 2,4,6-trimetilbenzil grubundan bir tanesi aren üzerinden metale koordine olmakta diğeri ise serbest kalmaktadır. Kelat oluşturmanın hangi koşullara bağlı olduğunu belirlemek amacıyla 2b ve 2c bileşikleri ve onlardan türeyen karben kompleksleri hazırlanmıştır. 2b bileşiği [RuCİ2(/?-simen)]2 ile etkileştiğinde /7-simen grubu rutenyu ederek 5 kompleksi oluşurken aynı olefin [RuCİ2(HMB)]2 ile 6 [RuCfeı kompleksini oluşturur. Bu 6 nolu bileşik 140 °C de ısıtıldığında HMB grubu rutenyumu terk ederek yine 5 nolu kompleks elde edilmektedir. Oysa, benzil içeren 2c, kelat yapı yerine beklenen karben komplekslerini (7 ve 8) vermiştir. I I CN N- i N N- ' ı l « R' 2 a R=CH2Mes; R'-CfyMes bR-CtyCfyOCH,; K=CH2Mes c R=CH2CH20CH3; R* = CH2Ph \ r c N Cl / CH,0 CH,0 CH,0 7 ı-N /T\ [ >-* I- N Cl CI OTf 9: R = CH2CH2OCH3 10: R=2,4,6-(CH3)3C6H2CH2 crço Sentezlenen kompleksler (3 ve 5) yeni rutenyum-aleniliden komplekslerine (9 ve 10) dönüştürülmüş ve bunların bazılarının dien siklik izomerizasyonunda ve halka kapanma metatez tepkimelerinde aktif katalizörler olduğu saptanmıştır. ANAHTAR KELİMELER: N-heterosiklik karben, rutenyum ve rodyum komple olefin metatezi, sildik izomerizasyon. ııÖğe Imidazolidinium ferrate complexes: Synthesis and catalytic properties(Elsevier France-Editions Scientifiques Medicales Elsevier, 2014) Demir, Serpil; Gokce, Yasemin; Roisnel, Thierry; Sortais, Jean-Baptiste; Darcel, Christophe; Ozdemir, IsmailThe new well-defined and air stable anionic iron complexes bearing an imidazolidinium ligand (2a-d) have been synthesized and characterized by elemental analysis and single-crystal X-ray diffraction studies. Starting from FeBr2, [imidazolidinium][FeBr4] complexes 2a and 2b were prepared. The reaction of imidazolidinium chlorides with Fe(OAc)(2), followed by a recrystallization in the air led to bis(imidazolidinium) mu-oxido-bis[trichloroferrate(III)] complexes 2c and 2d. The catalytic activity of these novel complexes has been evaluated in the cross-coupling reactions of alkyl halides with Grignard reagents. (C) 2014 Academie des sciences. Published by Elsevier Masson SAS. All rights reserved.Öğe Karben katalizli transfer hidrojenasyonuyla keton ve iminlerin indirgenmesi(2009) Özcan, Özge Emine; Demir, Serpil; Gürbüz, Nevin[Abstract Not Available]Öğe Kelat yapılı N-heterosiklik karben öncüllerinin sentezi ve katalitik özellikleri(İnönü Üniversitesi, 2007) Demir, Serpil[Abtsract Not Available]Öğe N-heterosiklik karben katalizli C-H/O-H bağ aktivasyonu ile biaril ve aromatik eter sentezi(2008) Özdemir, İsmail; Gürbüz, Nevin; Gök, Yetkin; Yiğit, Murat; Demir, Serpil; Yaşar, Sedat; Şahin, Neslihan[Abstract Not Available]Öğe N-heterosiklik-metal-karben katalizli C-N ve C-C bağ oluşum tepkimeleri(2006) Özdemir, İsmail; Alıcı, Bülent; Gürbüz, Nevin; Gök, Yetkin; Yiğit, Murat; Yiğit, Beyhan; Demir, SerpilSon yıllarda TV-heterosiklik karbenlerin geçiş metal kompleksleri dikkate değer bir ilgi odağı olmuştur. Bu kompleksler Pd katalizli Heck veya Suzuki eşleşme tepkimeleri, rodyum katalizli siklopropanasyon, hidroformilasyon, hidrojenasyon ve hidrosilasyon, rutenyum katalizli furanizasyon, metatez ve sikloizomerizasyon gibi önemli tepkimelerde katalizör olarak davranırlar. Bu nedenle yeni katalizörlerin hazırlanması çok önemlidir. Bu çalışmada 1-sübstitüye azol bileşikleri uygun alkil haloj emirlerle etkileştirilerek 7V-heterosiklik karben öncülleri, I, hazırlanmıştır. Bu karben öncülleri NaH ve KOBu' ile etkileştirilerek karşılık gelen III yapısındaki elektronca zengin olefinler sentezlenmiştir. Nükleofılik özelliğe sahip III yapısındaki entetraaminler elektrofılik özelliğe sahip geçiş metal bileşikleriyle etkileştirilip IV ve V yapısındaki 7V-heterosiklik karben-metal kompleksleri hazırlanmıştır. Ayrıca I tuzları Pd(OAc)2 ile etkileştirilerek II yapısındaki kompleksler elde edilmiştir.Hazırlanan bu tuzların ve metal-karben komplekslerinin, Heck ve Suzuki eşleşmeleri, aril boronik asitlerin aldehitlere katılması, asetofenonun hidrosilasyonu, ketonların hidrojen transferi, benzaldehitlerin arilasyonu, alilik. alkilasypn ve eterifikasyon tepkimelerindeki katalitik aktiviteleri incelenmiştir.Öğe New 1,2,4,5-tetrakis-(N-imidazoliniummethyl)benzene and 1,2,4,5-tetrakis(N-benzimidazoliummethyl)benzene salts as N-heterocyclic tetracarbene precursors: synthesis and involvement in ruthenium-catalyzed allylation reactions(Pergamon-Elsevier Science Ltd, 2010) Gurbuz, Nevin; Demir, Serpil; Ozdemir, Ismail; Cetinkaya, Bekir; Bruneau, ChristianNew tetraimidazolinium and tetrabenzimidazolium salts have been prepared Upon reaction with (BuOK)-Bu-t. they generate carbene ligands, which were associated in situ to [RuCp'(MeCN)(3)]PF6 to produce new ruthenium catalysts that are active for the Substitution of allylic substrates by amines, phenols, and carbonucleophiles The influence of the N-heterocyclic core as well as that of the N-substitutents at the periphery of the salts, on reactivity and regioselectivity have been exammed (C) 2009 Elsevier Ltd All rights reservedÖğe New photoactivatable CO-releasing molecules of manganese with imidazoline/benzimidazole ligands(Springer, 2014) Ustun, Elvan; Demir, Serpil; Ozdemir, Ismail; Schatzschneider, Ulrich[Abstract Not Available]Öğe Novel benzimidazolium salts and their silver complexes: Synthesis and antibacterial properties(Elsevier, 2012) Gunal, Selami; Kaloglu, Nazan; Ozdemir, Ilknur; Demir, Serpil; Ozdemir, IsmailA series of-unsymmetrical N,N-disubstituted benzimidazolium salts were synthesized as N-heterocyclic carbene (NHC) precursors. These compounds were used to synthesize of N-heterocyclic carbene silver(I) complexes. New compounds were characterized by NMR and IR spectroscopies and elemental analyses. The antibacterial activity of all the compounds was tested against Gram (+)/(-) and fungal strains using the agar dilution procedure. (C) 2012 Elsevier B.V. All rights reserved.
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