This book contains an overview of complex formation by macrocyclic ligand systems. Canadian journal of chemistry canadian science publishing. Macrocyclic phosphine compounds are sought after as ligands for transition metal complexes because of their strong binding properties. The study of macrocyclic chemistry represents a major area of activity which impinges on a range of other areas in both chemistry and biochemistry. Chapter 1 provides an overview of metalcarboxamide and pyridinamide chemistry including a number of important pincer compounds, macrocyclic involvement in formation of metaltemplated rotaxanes and catenanes, oxidation catalysts, anion receptors and bimetallic complexes. In particular, they are capable of stabilizing boxlike structures such as syn. Synthesis and coordination chemistry of macrocyclic phosphine. Synthesis, characterization and biological screening of some schiff. Macrocyclic ligands exhibit particularly high affinity for metal ions. In this paper, the synthesis and coordination chemistry of some macrocyclicbased tetranuclear metal complexes derived from the schiffbase na 4 l are investigated. The energetic basis for the macrocyclic effect can be most easily understood by comparing the relative stabilities of unbound macrocyclic ligands to openchain ligands as illustrated in fig. Since its birth, the development of macrocyclic chemistry has proceeded along two lines.
Magnetostructural correlation of the fe ii, co ii and ni ii complexes with l and with previously studied structurally similar ligands revealed a significant impact of the functional group in pendant arms on the magnetic anisotropy especially that of the co ii and ni ii complexes and some recommendations concerning the ligandfield design. An overview of essential concepts in supramolecular chemistry covering basic and applied reseach work. Written by wellknown experts from around the world, the topics of the chapters range. Lindoy, cambridge university press, cambridge, 1989. A lanthanide metalorganic framework based on a custom. Metal complexes of acyclic and macrocyclic multifunctional. Synthetic strategies toward sterically demanding macrocyclic ligands in order to prevent the formation of iron complexes of nuclearity higher than 2, a picketfence macrocyclic ligand, h2tipp4pim was designed. The importance of such complexes, for example to the mechanism of photosynthesis, or to the transport of oxygen in mammalian and other respiratory systems, has provided a motivation for investigation of the metalion. The polynuclear complexes mo 3 o 8 tidfdmso2h 2 o 1 and cu 2 tidf 2. As indicated in the figures, a free macrocyclic ligand in. The oxidation of cyclohexanone by the niiii complex of the macrocyclic ligand, 5,5,7,12,12,14hexamethyl1,4,8,11tetraazacyclotetradecanemeso14ane in acetonitrile solution containing cf 3 co 2 h obeyed the rate equation. In chemistry, a macrocyclic ligand is a macrocycle with a ring size of at least nine including all hetero atoms and three or more donor sites.
Toxic metal complexes of macrocyclic cyclen molecule. Coordination chemistry of macrocyclic compounds edwin c. Synthesis of 12membered tetraaza macrocyclic pyridinophanes bearing electronwithdrawing groups. The method also permits accurate evaluation of association equilibrium constants. The formation of ln 4 complexes results from the combined influence of the tetradentate coordination of the polycation by the portals of the macrocyclic ligand cb6 and the chelating effect of the carboxylate ligands of isonicotinic acid generated as a result of hydrolysis of 4.
Cyclic macromolecule or a macromolecular cyclic portion of a macromolecule note 1. Dicopper complexes of a macrocyclic ligand as models for. Macrocyclic ligand complexes are involved in a variety of fundamental biological systems. A template approach was used to prepare the ligand in a reasonable yield. New tetraazamacrocyclic ligands the macrocycles cyclen and cyclam 12anen 4 and 14anen 4 have been known for several decades, and their complexation chemistry with a large variety of metal ions has been studied thoroughly. Ir spectra of macrocyclic ligand and its complex pdl 1h nmr spectra the 1hnmr spectrum of the macrocyclic ligand shows triplet in the region. Biomedical applications of macrocyclic ligand complexes. Synthesis and characterization of ironiii, cobaltii and nickelii metal complexes with tahhdap and tahhtda hexadentate macrocyclic ligands. G always favours formation of macrocyclic complex log k 1 23. As such, these ligands are particularly useful in applications where robust transition metalphosphine complexes are employed, as in homogeneous catalysis or in radiopharmaceuticals. Kinetic and spectral studies in the presence of cf 3 co 2 na indicate the inhibition term in cf 3. Fenton and others published the chemistry of macrocyclic ligand complexes edited by l.
The study of metal complexes of macrocyclic ligands appears to. Macrocyclic ligands that can incorporate two or more metal ions giving homo or heterodinuclear complexes are of considerable interest. All except two au complexes were characterized using singlecrystal xray diffraction. The chemistry of macrocyclic ligand complexes by l. The chemistry of macrocyclic ligand complexes cambridge texts. Chemistry of dinucleating macrocyclic ligand and their. It covers the common types and the main strategies for the synthesis of. Coordination chemistry of macrocyclic ligands request pdf. Three new complexes niii, cuii and coii were synthesized of macrocyclic ligand derived from 1, 4dicarbonylphenyldihydrazide and ophthalaldehyde in the ratio of 2. Note in these figures that the coordinated macrocyclic and openchain complexes have been arbitrarily set at equal energies. Metal complexes of acyclic and macrocyclic multifunctional ligands.
Leonard f lindoy this book contains an overview of complex formation by macrocyclic ligand systems. These new tetrapyrrole nickel and cobalt complexes display strong light absorptivity and rich multielectron redox chemistry. Synthesis and characterization of complex 1051 figure 1. Synthesis of 14membered tetraazamacrocyclic ligand. Electrochemical studies of synthetic models of copper proteins. The tlc of all the ligand and complexes confirmed their purity. Some other common chelating and cyclic ligands are shown below. The chemistry of macrocyclic ligand complexes cambridge. In the literature, the term macrocycle is sometimes used for molecules of low relative molecular mass that would not be considered macromolecules. Examples include photosynthesis, which proceeds due to the magnesium macrocycle chlorophyll, and various electron transfer reactions which occur in cytochromes.
Such macrocyclic ligands often lead to complexes with enhanced thermodynamic and kinetic stability with respect to metal ion. Synthesis and coordination chemistry of macrocyclic. Tetranuclear lanthanide aqua hydroxo complexes with. Synthesis, characterization, and antibacterial activity of. Some of these heterodinuclear complexes are interesting as they mimic the active sites of metalloenzymes, such as cytochromec oxidase and bovine erythrocyte superoxide dismutase. Isbn 052125261x the study of macrocycles and their complexes has developed rapidly in recent years, coming of age with the award of the 1987 nobel prize in chemistry to three of its leading practitioners. Chemistry of dinucleating macrocyclic ligand and their complexes.
Coordination chemistry of macrocyclic compounds gordon. Preparation of macrocyclic complexes the ability of certain transition metals, especially nickel, to act as a template in intermolecular schiffbase reactions into macrocycle formation is well known3, 4. What is different about macrocyclic ligand complexes. Stoichiometric and metaldeficient copperii complexes of. This idea is further supported by the presence of a broad ligand. This popularity may be due to the complexes high thermodynamic stability, relative kinetic inertness, basicity, transition metalion coordinating ability, and rigid structure 6. Fourteen agi, aui, niii, pdii, and ptii complexes with macrocyclic tetradentate nheterocyclic carbene nhc ligands were prepared via reactions between three macrocyclic tetrabenzimidazolium salts and metal precursors.
The chemistry of macrocyclic ligand complexes edited by l. Trivalent chromium, manganese and iron salts react in situ with 2,6diacetylpyridine and 1,2diaminobenzene to form complexes containing a 18membered. The crystal and molecular structure of lcu2ch3co22clo425h2o. The crystal structures of the compounds show a packing of 1.
Stable octahedral, lowspin nickeliii complexes of a. Lindoy, the chemistry of macrocyclic ligand complexes, cambridge university press, cambridge 1989. Generally, macrocyclic polyamides are prepared by reaction of polyamine with either the diester salt of dicarboxylic acid or the dicarboxylicacid dichloride 24. Binuclear complexes of a new hexadentate macrocyclic ligand. The first example of cobalt dimethylisocorrole was also demonstrated. Formation constants for complexion between alkali metal cations and the crown ether 18c6 in the solvent 2cyanopyridine at 3ooc were determined from conductance measurements. Distinctive coordination chemistry and biological significance of complexes with macrocyclic ligands. Synthesis and characterization of complex compounds of. Density functional calculations are used to elucidate the reaction mechanism of water oxidation catalyzed by iron tetraamido macrocyclic ligand taml complexes. Macrocyclic compounds have attracted increasing interest owing to their mixed softhard donor character, versatile coordination behavior and in the understanding of molecular processes. Diffraction results have yielded three molecular structures, cd12ane. Metal complexes of macrocyclic ligands containing pyridine. This book contains an overview of the macrocyclic ligand systems and discusses the structure and properties of macrocyclic systems.
The chemistry of macrocyclic ligands has been known for several decades 1. Cambridge core molecular biology, biochemistry, and structural biology the chemistry of macrocyclic ligand complexes by l. The chemistry of macrocyclic ligand complexes ebook, 1989. Nature chooses macrocyclic derivatives which give enhanced kinetic and thermodynamic stabilities, such that the metal ion. Synthesis of nnnn tetradentate macrocyclic ligand and its pdii, ptii, ruiii, and iriii complexes. The study of macrocyclic ligand systems represents a major activity impinging on a wide range of areas in chemistry and biochemistry. Cucurbituril as a new macrocyclic ligand for complexation. Coordination chemistry of macrocyclic compounds springerlink. Polyazamacrocycles represent a popular class of macrocyclic ligands for supramolecular chemistry and crystal engineering. Mobilities of cationmacrocyclic ligand complexes 1535 in eq. New copper and oxomolybdate robsontype polynuclear. The study of macrocyclic chemistry represents a major area of activity which impinges on a range of other areas in.
Current trends and future perspectives illustrates essential concepts in this expanding research field covering both basic and applied studies. This chapter discusses the progress towards the synthesis of this ligand as well as design strategies. This book describes the coordination chemistry of macrocyclic ligands. The text discusses the structures and properties of macrocyclic. Metal complexes of ditopic and polytopic macrocyclic ligands. Electrochemical co2 and o2 reduction using nickel and. The macrocyclic ligand c 16 h 38 n 4 o 2 br 2 4was synthesised by mixingammonium salt0. Synthesis of nnnn tetradentate macrocyclic ligand and its. The synthesis of compounds which may serve as model systems for some natural products containing large rings as ligands provided the main goal for the early expansion of research effort. Field spectra and magnetic properties of synthetic macrocyclic complexes. Research in medicinal inorganic chemistry has expanded in recent years by exploiting a variety of chelating ligands to modify and control the properties of metal ions in biological systems. The fact that macrocyclic ligand complexes are involved in a number of fundamental biological systems has long been recognized. The selectivity of the macrocyclic ligands that contain combination of oxo o, aza n, phospha p and sulpha s for the extraction of metal ions depends on the ligand flexibility, nature of the ligand backbone, the cavity size of the macrocyclic core, nature and number of donor atoms in addition to their relative position in the macrocyclic.
The field has characteristically yielded many interesting and unusual compounds. Three novel complexes of cuii, coii and znii using macrocyclic ligand derived by the condensation of diethyl phthalate and. Get your kindle here, or download a free kindle reading app. The magnesium complex 1 of the tetranucleating macrocyclic ligand h4l1 on transmetalation with copperii perchlorate in the presence of triethylamine produces the dicopperii complex 3 of the dinucleating macrocyclic ligand h2l3, while the same reaction when carried out in absence of triethylamine affords the metaldeficient compound 4 derived from h2l3. Synthesis and reactivity in inorganic, metalorganic, and nanometal chemistry. Synthesis and reactivity in inorganic and metalorganic chemistry, vol. The unique photophysical and redox properties of the complexes were shown due to great metal ligand cooperativity by dft and tddft calculations. Macrocyclic chelators offer the benefit of high stability complex formation and, through functionalization, the opportunity to fine tune the coordination environment. Buy the chemistry of macrocyclic ligand complexes cambridge texts in chemistry and.
The method allows for precise determination of these formation constants up to values of kf. Of the many macrocyclic template reactions, the preparation of geodkens macrocycle 2 is particularly attractive6 for the. Synthesis and structural characterization of metal. A cyclic macromolecule has no endgroups but may nevertheless be regarded as a chain.
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