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Articles 5461 - 5490 of 10319
Full-Text Articles in Physical Sciences and Mathematics
Some Identities For The Glasser Transform And Their Applications, Faruk Uçar
Some Identities For The Glasser Transform And Their Applications, Faruk Uçar
Turkish Journal of Mathematics
In the present paper we consider a new integral transform, denoted by $\mathcal{G}_{\nu}$, which may be regarded as a generalization of the well-known transform due to Glasser. Many identities involving this transform are given. By making use of these identities, a number of new Parseval--Goldstein type identities are obtained for these and many other well-known integral transforms. The identities proven in this paper are shown to give rise to useful corollaries for evaluating infinite integrals of special functions. Some examples are also given as illustrations of the results presented here.
Existence Of Solutions For A First-Order Nonlocal Boundary Value Problem With Changing-Sign Nonlinearity, Erbi̇l Çeti̇n, Fatma Serap Topal
Existence Of Solutions For A First-Order Nonlocal Boundary Value Problem With Changing-Sign Nonlinearity, Erbi̇l Çeti̇n, Fatma Serap Topal
Turkish Journal of Mathematics
This work is concerned with the existence of positive solutions to a nonlinear nonlocal first-order multipoint problem. Here the nonlinearity is allowed to take on negative values, not only positive values.
On Certain Minimal Non-$\Mathfrak{Y}$-Groups For Some Classes $\Mathfrak{Y}$, Ahmet Arikan, Selami̇ Ercan
On Certain Minimal Non-$\Mathfrak{Y}$-Groups For Some Classes $\Mathfrak{Y}$, Ahmet Arikan, Selami̇ Ercan
Turkish Journal of Mathematics
Let $\{\theta_n\}_{n=1}^\infty$ be a sequence of words. If there exists a positive integer $n$ such that $\theta_m(G)=1$ for every $m\geq n$, then we say that $G$ satisfies (*) and denote the class of all groups satisfying (*) by $\mathfrak{X}_{\{\theta_n\}_{n=1}^\infty}$. If for every proper subgroup $K$ of $G$, $K\in \mathfrak{X}_{\{\theta_n\}_{n=1}^\infty}$ but $G\notin\mathfrak{X}_{\{\theta_n\}_{n=1}^\infty}$, then we call $G$ a minimal non-$\mathfrak{X}_{\{\theta_n\}_{n=1}^\infty}$-group. Assume that $G$ is an infinite locally finite group with trivial center and $\theta_i(G)=G$ for all $i\geq 1$. In this case we mainly prove that there exists a positive integer $t$ such that for every proper normal subgroup $N$ of $G$, either …
The Prime Tournaments $T$ With $\Mid\! W_{5}(T) \!\Mid = \Mid\! T \!\Mid -2$, Houmem Belkhechine, Imed Boudabbous, Kaouthar Hzami
The Prime Tournaments $T$ With $\Mid\! W_{5}(T) \!\Mid = \Mid\! T \!\Mid -2$, Houmem Belkhechine, Imed Boudabbous, Kaouthar Hzami
Turkish Journal of Mathematics
We consider a tournament $T=(V, A)$. For $X\subseteq V$, the subtournament of $T$ induced by $X$ is $T[X] = (X, A \cap (X \times X))$. A module of $T$ is a subset $X$ of $V$ such that for $a, b\in X$ and $ x\in V\setminus X$, $(a,x)\in A$ if and only if $(b,x)\in A$. The trivial modules of $T$ are $\emptyset$, $\{x\}(x\in V)$, and $V$. A tournament is prime if all its modules are trivial. For $n\geq 2$, $W_{2n+1}$ denotes the unique prime tournament defined on $\{0,\dots,2n\}$ such that $W_{2n+1}[\{0,\dots,2n-1\}]$ is the usual total order. Given a prime tournament $T$, …
Moduli Spaces Of Arrangements Of 11 Projective Lines With A Quintuple Point, Meirav Amram, Cheng Gong, Mina Teicher, Wan-Yuan Xu
Moduli Spaces Of Arrangements Of 11 Projective Lines With A Quintuple Point, Meirav Amram, Cheng Gong, Mina Teicher, Wan-Yuan Xu
Turkish Journal of Mathematics
In this paper, we try to classify moduli spaces of arrangements of 11 lines with quintuple points. We show that moduli spaces of arrangements of 11 lines with quintuple points can consist of more than 2 connected components. We also present defining equations of the arrangements whose moduli spaces are not irreducible after taking quotients by the complex conjugation by Maple and supply some "potential Zariski pairs".
Uniquely Strongly Clean Triangular Matrices, Huanyin Chen, Orhan Gürgün, Handan Kose
Uniquely Strongly Clean Triangular Matrices, Huanyin Chen, Orhan Gürgün, Handan Kose
Turkish Journal of Mathematics
A ring $R$ is uniquely (strongly) clean provided that for any $a\in R$ there exists a unique idempotent $e\in R$ \big($e\in comm(a)$\big) such that $a-e\in U(R)$. We prove, in this note, that a ring $R$ is uniquely clean and uniquely bleached if and only if $R$ is abelian, ${\mathbb{T}}_{n}(R)$ is uniquely strongly clean for all $n\geq 1$, i.e. every $n\times n$ triangular matrix over $R$ is uniquely strongly clean, if and only if $R$ is abelian, and ${\mathbb{T}}_{n}(R)$ is uniquely strongly clean for some $n\geq 1$. In the commutative case, more explicit results are obtained.
Quadratic Recursive Towers Of Function Fields Over $\Mathbb{F}_2$, Henning Stichtenoth, Seher Tutdere
Quadratic Recursive Towers Of Function Fields Over $\Mathbb{F}_2$, Henning Stichtenoth, Seher Tutdere
Turkish Journal of Mathematics
Let $\FF=(F_n)_{n\geq 0}$ be a quadratic recursive tower of algebraic function fields over the finite field $\F_2$, i.e. $\FF$ is a recursive tower such that $[F_n:F_{n-1}]=2$ for all $n\geq 1$. For any integer $r\geq 1$, let $\beta_r(\FF):=\lim_{n\to \infty} B_r(F_n)/g(F_n)$, where $B_r(F_n)$ is the number of places of degree $r$ and $g(F_n)$ is the genus, respectively, of $F_n/\F_2$. In this paper we give a classification of all rational functions $f(X,Y)\in \F_2(X,Y)$ that may define a quadratic recursive tower $\FF$ over $\F_2$ with at least one positive invariant $\beta_r(\FF)$. Moreover, we estimate $\beta_1(\FF)$ for each such tower.
Split Extension Classifiers In The Category Of Precrossed Modules Of Commutative Algebras, Yaşar Boyaci, Tufan Sai̇t Kuzpinari, Enver Önder Uslu
Split Extension Classifiers In The Category Of Precrossed Modules Of Commutative Algebras, Yaşar Boyaci, Tufan Sai̇t Kuzpinari, Enver Önder Uslu
Turkish Journal of Mathematics
We construct an actor of a precat$^{1}$-algebra and then by using the natural equivalence between the categories of precat$^{1}$-algebras and that of precrossed modules, we construct the split extension classifier of the corresponding precrossed module, which gives rise to the representability of actions in the category of precrossed modules of commutative algebras under certain conditions.
Defect Polynomials And Tutte Polynomials Of Some Asymmetric Graphs, Eunice Mphako-Banda, Toufik Mansour
Defect Polynomials And Tutte Polynomials Of Some Asymmetric Graphs, Eunice Mphako-Banda, Toufik Mansour
Turkish Journal of Mathematics
We give explicit expressions of the Tutte polynomial of asymmetric complete flower graph and asymmetric incomplete flower graph. We then express these Tutte polynomials as generating functions and decode some valuable information about the asymmetric complete flower graph and asymmetric incomplete flower graph. Furthermore, we convert the Tutte polynomials into coboundary polynomials and give explicit expressions of the $k$-defect polynomials of these structures. Finally, we conclude that nonisomorphic graphs in this class have the same Tutte polynomials, the same chromatic polynomials, and the same defect polynomials.
On Pseudohyperbolic Space Motions, Tunahan Turhan, Nural Yüksel, Ni̇hat Ayyildiz
On Pseudohyperbolic Space Motions, Tunahan Turhan, Nural Yüksel, Ni̇hat Ayyildiz
Turkish Journal of Mathematics
In the present paper, the geometrical instantaneous invariants of the motion $H_{_{m}}/H_{_{f}}\ $in dual Lorentzian $3$-space are determined. Depending on this, the dual Lorentzian instantaneous screw axis of the motion of $K_{_{m}}$ with respect to the dual pseudohyperbolic space $K_{_{m}}$ is constructed. On the other hand, we show that, in each position of $H_{_{m}}$, the fixed and moving axodes have the instantaneous screw axis of this position in common. We also give relations between the geodetic curvature and the curvature of the polodes.
Classification Of Metallic Shaped Hypersurfaces In Real Space Forms, Ci̇han Özgür, Ni̇hal Yilmaz Özgür
Classification Of Metallic Shaped Hypersurfaces In Real Space Forms, Ci̇han Özgür, Ni̇hal Yilmaz Özgür
Turkish Journal of Mathematics
We define the notion of a metallic shaped hypersurface and give the full classification of metallic shaped hypersurfaces in real space forms. We deduce that every metallic shaped hypersurface in real space forms is a semisymmetric hypersurface.
Generalized Chebyshev Polynomials Of The Second Kind, Mohammad A. Alqudah
Generalized Chebyshev Polynomials Of The Second Kind, Mohammad A. Alqudah
Turkish Journal of Mathematics
We characterize the generalized Chebyshev polynomials of the second kind (Chebyshev-II), and then we provide a closed form of the generalized Chebyshev-II polynomials using the Bernstein basis. These polynomials can be used to describe the approximation of continuous functions by Chebyshev interpolation and Chebyshev series and how to efficiently compute such approximations. We conclude the paper with some results concerning integrals of the generalized Chebyshev-II and Bernstein polynomials.
Existence Of Unique Solution To Switchedfractional Differential Equations With $P$-Laplacian Operator, Xiufeng Guo
Existence Of Unique Solution To Switchedfractional Differential Equations With $P$-Laplacian Operator, Xiufeng Guo
Turkish Journal of Mathematics
In this paper, we study a class of nonlinear switched systems of fractional order with $p$-Laplacian operator. By applying a fixed point theorem for a concave operator on a cone, we obtain the existence and uniqueness of a positive solution for an integral boundary value problem with switched nonlinearity under some suitable assumptions. An illustrative example is included to show that the obtained results are effective.
Special Proper Pointwise Slant Surfaces Of A Locally Product Riemannian Manifold, Mehmet Gülbahar, Erol Kiliç, Semra Saraçoğlu Çeli̇k
Special Proper Pointwise Slant Surfaces Of A Locally Product Riemannian Manifold, Mehmet Gülbahar, Erol Kiliç, Semra Saraçoğlu Çeli̇k
Turkish Journal of Mathematics
The structure of pointwise slant submanifolds in an almost product Riemannian manifold is investigated and the special proper pointwise slant surfaces of a locally product manifold are introduced. A relation involving the squared mean curvature and the Gauss curvature of pointwise slant surface of a locally product manifold is proved. Two examples of proper pointwise slant surfaces of a locally product manifold, one of which is special and the other one is not special, are given.
Optimality Criteria For Sum Of Fractional Multiobjective Optimization Problem With Generalized Invexity, Deepak Bhati, Pitam Singh
Optimality Criteria For Sum Of Fractional Multiobjective Optimization Problem With Generalized Invexity, Deepak Bhati, Pitam Singh
Turkish Journal of Mathematics
The sum of a fractional program is a nonconvex optimization problem in the field of fractional programming and it is difficult to solve. The development of research is restricted to single objective sums of fractional problems only. The branch and bound methods/algorithms are developed in the literature for this problem as a single objective problem. The theoretical and algorithmic development for sums of fractional programming problems is restricted to single objective problems. In this paper, some new optimality conditions are proposed for the sum of a fractional multiobjective optimization problem with generalized invexity. The optimality conditions are obtained by using …
Some Properties Of A Class Of Analytic Functions Defined Bygeneralized Struve Functions, Mohsan Raza, Ni̇hat Yağmur
Some Properties Of A Class Of Analytic Functions Defined Bygeneralized Struve Functions, Mohsan Raza, Ni̇hat Yağmur
Turkish Journal of Mathematics
The aim of this paper is to define \ a new operator by using the generalized Struve functions $\sum\limits_{n=0}^{\infty }\frac{\left( -c/4\right) ^{n}}{\left( 3/2\right) _{n}\left( k\right) _{n}}z^{n+1}$ with $% k$ $=p+$ $\left( b+2\right) /2\neq 0,-1,-2,\ldots $ and $b,c,k\in \mathbb{C} $. By using this operator we define a subclass of analytic functions. We discuss some properties of this class such as inclusion problems, radius problems, and some other interesting properties related to this operator.
On The Classification Of Almost Null Rings, Ryszard Andruszkiewicz, Karol Pryszczepko
On The Classification Of Almost Null Rings, Ryszard Andruszkiewicz, Karol Pryszczepko
Turkish Journal of Mathematics
An almost null ring is a ring $R$ in which for all $a,b\in R$, $a^3=0$, $Ma^2=0$ for some square-free integer $M$ that depends on $a$ and $ab= ka^{2}=l b^{2}$ for some integers $k,l$. This paper is devoted to the classification of the almost null rings.
On Metallic Riemannian Structures, Aydin Gezer, Çağri Karaman
On Metallic Riemannian Structures, Aydin Gezer, Çağri Karaman
Turkish Journal of Mathematics
The paper is devoted to the study of metallic Riemannian structures. An integrability condition and curvature properties for these structures by means of a $\Phi $-operator applied to pure tensor fields are presented. Examples of these structures are also given.
Magnetic Curves On Flat Para-K\"Ahler Manifolds, Mohamed Jleli, Marian Ioan Munteanu
Magnetic Curves On Flat Para-K\"Ahler Manifolds, Mohamed Jleli, Marian Ioan Munteanu
Turkish Journal of Mathematics
In this paper we prove that spacelike and timelike magnetic trajectories corresponding to the para-K\"ahler 2-form on a para-K\"ahler manifold $(M,\p,g)$ are circles on $M$. We then classify all para-K\"ahler magnetic curves in pseudo-Euclidean spaces ${\mathbb{E}}^{2n}_n$.
Equivalencies Between Beta-Shifts And S-Gap Shifts, Dawoud Ahmadi Dastjerdi, Somayyeh Jangjoo Shaldehi
Equivalencies Between Beta-Shifts And S-Gap Shifts, Dawoud Ahmadi Dastjerdi, Somayyeh Jangjoo Shaldehi
Turkish Journal of Mathematics
Let X_{\beta} be a \beta -shift for \beta \in (1, 2] and X(S) a S-gap shift for S\subseteq N \cup {0}. We show that if X_\beta is SFT (resp. sofic), then there is a unique S-gap shift conjugate (resp. right-resolving almost conjugate) to this X_\beta, and if X_\beta is not SFT, then no S-gap shift is conjugate to X_\beta. For any synchronized X_{\beta} , an X(S) exists such that X_{\beta} and X(S) have a common synchronized 1-1 a.e. extension. For a nonsynchronized X_\beta, this common extension is just an almost Markov synchronized system with entropy preserving maps. We then compute …
Simultaneous Analysis Of Losartan, Its Active Metabolite, And Hydrochlorothiazide In Human Plasma By A Uplc-Ms/Ms Method, Priyanka A. Shah, Primal Sharma, Jaivik V. Shah, Mallika Sanyal, Pranav S. Shrivastav
Simultaneous Analysis Of Losartan, Its Active Metabolite, And Hydrochlorothiazide In Human Plasma By A Uplc-Ms/Ms Method, Priyanka A. Shah, Primal Sharma, Jaivik V. Shah, Mallika Sanyal, Pranav S. Shrivastav
Turkish Journal of Chemistry
A selective and sensitive ultra performance liquid chromatography-tandem mass spectrometry method was developed for the simultaneous determination of losartan (LOS), EXP-3174, which is an active metabolite LOS carboxylic acid, and hydrochlorothiazide (HCTZ) in human plasma. Solid-phase extraction was carried out on Oasis HLB cartridges with 100 $\mu $L of plasma to give an extraction recovery in the range of 88.5%-102.5% for the three analytes. Chromatography on a BEH C18 column afforded baseline separation of all the analytes within 2.4 min using 1.0% formic acid in water and acetonitrile (15:85, v/v) as the mobile phase. Quantitation was performed with multiple reaction …
Conversion Of Racemic Allylic Hydroperoxides Into Corresponding Chiral 1/2,3-Triols By Using Catalytic Oso$_{4}$ And Chiral Cinchona Ligands In The Absence Of Co-Oxidant, Haydar Göksu, Mehmet Serdar Gülteki̇n
Conversion Of Racemic Allylic Hydroperoxides Into Corresponding Chiral 1/2,3-Triols By Using Catalytic Oso$_{4}$ And Chiral Cinchona Ligands In The Absence Of Co-Oxidant, Haydar Göksu, Mehmet Serdar Gülteki̇n
Turkish Journal of Chemistry
For the first time, removal of oxygen atoms from allylic hydroperoxide functionality and reintroduction to the double bond was achieved using catalytic OsO$_{4}$ and chiral cinchona alkaloid derivatives in an acetone-water mixture to give corresponding chiral 1/2,3-triol with an enantioselectivity up to 99% ee. The hydroperoxide group was used as both a co-oxidant and a source of hydroxyl groups. This protocol is thought to have potential to provide opportunities for chiral synthesis of 1/2,3-triols from corresponding allylic hydroperoxides in the absence of co-oxidant in one stage for the first time in the literature.
A Water-Soluble Perylene Derivative For Live-Cell Imaging, Yongshan Ma, Fengxia Zhang, Jinfeng Zhang, Tianyi Jiang
A Water-Soluble Perylene Derivative For Live-Cell Imaging, Yongshan Ma, Fengxia Zhang, Jinfeng Zhang, Tianyi Jiang
Turkish Journal of Chemistry
Glutamic functionalized water-soluble perylene diimide, N, N'-di (L-glutamic amine)-perylene-3,4,9,10-tetracarboxylic diimide (GAPTCD) has three absorbance maxima at 469, 498, and 534 nm and two emission peaks at 550 and 587 nm. Owing to the highly negative electrostatic potential of the perylene plane, the perylene derivative showed good water solubility and strong fluorescence in alkali and neutral solutions. Both the absorbance and emission intensities decreased with the decreasing of pH from 9.66 to 5.92. This could be ascribed to the $\pi -\pi $ stacking produced by H$^{+}$ at the carboxyl group due to its electron accepting nature. Electrostatic potential maps also indicated …
Synthesis And Biological Evaluation Of A New Series Of 4-Alkoxy-2-Arylquinoline Derivatives As Potential Antituberculosis Agents, Gonca Tosun, Tayfun Arslan, Zeynep İskefi̇yeli̇, Murat Küçük, Şengül Alpay Karaoğlu, Nuretti̇n Yayli
Synthesis And Biological Evaluation Of A New Series Of 4-Alkoxy-2-Arylquinoline Derivatives As Potential Antituberculosis Agents, Gonca Tosun, Tayfun Arslan, Zeynep İskefi̇yeli̇, Murat Küçük, Şengül Alpay Karaoğlu, Nuretti̇n Yayli
Turkish Journal of Chemistry
Three new series of 33 quinolone compounds, 2-(2-, 3-, and 4-fluorophenyl)-4-O-alkyl(C$_{5-15})$quinolines (7a-k, 8a-k, and 9a-k), were synthesized from 2-(2-, 3-, and 4-fluorophenyl)-2,3-dihydroquinolin-4(1H)-one (4, 5, and 6) by the reaction of alkyl halides under basic conditions in DMF. The new compounds 7a-k, 8a-k, and 9a-k were synthesized from flavonones 4-6, which can be considered new precursors for quinoline synthesis through a one-step reaction. All the target compounds (7a-k, 8a-k, and 9a-k) were evaluated for their in vitro antimicrobial activity against nine test microorganisms. They showed the most activity against Mycobacterium smegmatis with minimum inhibitory concentrations (MIC) of 62.5-500 $\mu $g/mL, indicating …
Influence Of Acid And Heavy Metal Cation Exchange Treatments On Methane Adsorption Properties Of Mordenite, Meryem Sakizci, Leyla Özgül Kilinç
Influence Of Acid And Heavy Metal Cation Exchange Treatments On Methane Adsorption Properties Of Mordenite, Meryem Sakizci, Leyla Özgül Kilinç
Turkish Journal of Chemistry
In this study, the adsorption of methane (CH$_{4})$ capacities onto natural mordenite obtained from \.{I}zmir, Turkey, and its cationic forms (CuM, AgM, FeM, and HM samples) were investigated at the temperatures of 0 and 25 $^{\circ}$C up to 100 kPa. Natural and modified samples were characterized by X-ray diffraction (XRD), X-ray fluorescence (XRF), Fourier transform infrared (FT-IR), thermogravimetry (TG-DTG), differential thermal analysis (DTA), scanning electron microscopy (SEM) coupled with energy dispersion spectroscopy (EDS), and N$_{2}$ adsorption methods. Quantitative XRD analysis showed that the major component of the natural zeolite was mordenite, together with minor amounts of quartz, feldspar, and clay …
New Tetrazolic Azo Dyes Linked To (Thio)Barbiturate And Electron-Rich Aromatics As Potential Antimicrobial Agents, Nader Noroozi Pesyan, Davoud Soleimani, Nima Hosseini Jazani
New Tetrazolic Azo Dyes Linked To (Thio)Barbiturate And Electron-Rich Aromatics As Potential Antimicrobial Agents, Nader Noroozi Pesyan, Davoud Soleimani, Nima Hosseini Jazani
Turkish Journal of Chemistry
A series of new tetrazolic azo dyes based on (thio)barbiturate and electron-rich aromatics were synthesized in excellent yield. The electron-donor and tetrazole ring moieties were linked by a $p$-phenylazo bridge and the structural characterizations were achieved by FT IR, $^{1}$H and $^{13}$C NMR, and UV-visible spectrometry. The antibacterial activity of the synthesized compounds was tested against gram-positive and gram-negative bacterial strains, namely \textit{Acinetobacter calcoaceticus} (ATCC23055), \textit{Escherichia coli} (ATCC2592), \textit{Pseudomonas aeruginosa} (ATCC27853), and \textit{Staphylococcus aureus} (ATCC25923). As a result, potential antimicrobial effects were seen for some of the synthesized compounds.
Synthesis, Characterization, And Electrical And Optical Properties Of Magnesium-Type Boracite, Tuğba İbroşka, Azmi̇ Seyhun Kipçak, Süreyya Aydin Yüksel, Emek Derun, Sabri̇ye Pi̇şki̇n
Synthesis, Characterization, And Electrical And Optical Properties Of Magnesium-Type Boracite, Tuğba İbroşka, Azmi̇ Seyhun Kipçak, Süreyya Aydin Yüksel, Emek Derun, Sabri̇ye Pi̇şki̇n
Turkish Journal of Chemistry
Synthesis of the magnesium type of the mineral boracite (Mg$_{3}$B$_{7}$O$_{13}$Cl) was studied. Several parameters affecting boracite synthesis were investigated. The raw materials selected were magnesium chloride hexahydrate (MgCl$_{2}$.6H$_{2}$O), magnesium oxide (MgO), and boron oxide (B$_{2}$O$_{3})$. Reaction temperatures were selected between 600~$^{\circ}$C and 900 $^{\circ}$C. Moreover, three different reaction times of 4, 1, and 0.5 h were studied with the determined optimum molar ratio, reaction temperature, and reaction medium. Synthesized boracite characterization analyses were done by the techniques of X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), and scanning electron microscope (SEM). Reaction yields were also calculated. From the results of …
Corrosion Inhibition By Naturally Occurring Hibiscus Sabdariffa Plant Extract On A Mild Steel Alloy In Hcl Solution, Magda Abdo Mahmoud Ameer, Amany Mohamed Fekry
Corrosion Inhibition By Naturally Occurring Hibiscus Sabdariffa Plant Extract On A Mild Steel Alloy In Hcl Solution, Magda Abdo Mahmoud Ameer, Amany Mohamed Fekry
Turkish Journal of Chemistry
The corrosion inhibition of mild steel alloys is of tremendous technological importance due to their increased industrial applications. Potentiodynamic polarization and electrochemical impedance spectroscopy techniques were used to establish the effect of different concentrations of HCl on the corrosion behavior of mild steel. A study was conducted on the inhibition of dissolution for a mild steel alloy in the most corrosive concentration of HCl (5 M) by adding different concentrations of aqueous extract of \textit{Hibiscus sabdariffa} plant (named karkade or rosselle) as an ecofriendly inhibitor. The extent of corrosion inhibition as measured by the two techniques was comparable. The results …
Contribution Of Heterobifunctional Ligands To Transition Metal-Catalysed C--C Coupling Reactions, Agnes Labande, Eric Deydier, Eric Manoury, Jean-Claude Daran, Catherine Audin, Rinaldo Poli
Contribution Of Heterobifunctional Ligands To Transition Metal-Catalysed C--C Coupling Reactions, Agnes Labande, Eric Deydier, Eric Manoury, Jean-Claude Daran, Catherine Audin, Rinaldo Poli
Turkish Journal of Chemistry
In this account the authors' latest results in C-C coupling catalysis are reviewed. First, an efficient catalytic system for the Kumada-Tamao-Corriu coupling reaction based on NHC-phosphine (NHC = N-heterocyclic carbene) nickel complexes is presented. Then the use of palladium complexes of chiral ferrocenyl NHC-phosphines in the asymmetric Suzuki-Miyaura coupling reaction is reported. High catalytic activities and moderate enantioselectivities (ee up to 46%) were obtained. Chiral ferrocenyl phosphine-ethers were also tested in the asymmetric Suzuki-Miyaura reaction yielding good activities and moderate enantioselectivities (ee up to 37%). Finally, the original synthesis of a ferrocenyl rhodium(III) complex and its successful use as catalyst …
Cross Coupling Reactions Catalyzed By (Nhc)Pd(Ii) Complexes, Nevi̇n Gürbüz, Emi̇ne Özge Karaca, İsmai̇l Özdemi̇r, Beki̇r Çeti̇nkaya
Cross Coupling Reactions Catalyzed By (Nhc)Pd(Ii) Complexes, Nevi̇n Gürbüz, Emi̇ne Özge Karaca, İsmai̇l Özdemi̇r, Beki̇r Çeti̇nkaya
Turkish Journal of Chemistry
This review is focused on new developments reported during the last 3 years concerning the catalytic performances of in situ formed or preformed NHC--Pd(II) complexes (NHC: $N$-heterocyclic carbene) for cross-coupling reactions such as Heck--Mizoraki (often shortened to the Heck reaction), Kumada, Negishi, Suzuki--Miyaura (often shortened to the Suzuki reaction), Sonogashira and Hiyama couplings, and the Buchwald--Hartwig aminations, which are extremely powerful in the formation of C--C and C--heteroatom bonds. Due to the great number of publications and limited space here, we made a special attempt to compile the relevant data in tables, which we hope will serve as a guide …