Iridiumcatalysed regioselective borylation of carboranes. Based on its ability to quantitatively protonate benzene, the chlorinated carborane acid hchb 11 cl 11 was conservatively estimated to have an h 0 value at or below. Safety data sheet ghs product identifier other means of identification emergency telephone number with hours of operation section 1. Synthesis, characterization, and thermal behavior of. One common measure of acid strength for concentrated, superacidic liquid media is the hammett acidity function, h 0. Carboranyl derivatives of platinum and tin and some metallacarboranes exhibit activity against malignant tumors. Carboranes as guests, counterions and linkers in coordination polymers and networks catherine e. Functionalization of the multiple, similar, boronhydrogen bonds in carboranes is difficult to achieve with selectivity. Tjarks, carborane clusters in computational drug design. Because diborane is a gas a ambient temperature, the mostlikely exposure routes are inhalation. More recently, work has begun to exploit the unique chemical and physical properties of carboranes for the preparation of novel inorganic pharmaceuticals and biological probes. Carboranes and metallacarboranes hypercarbon chemistry. Carboranes larger than 14 vertexes containing only carbon and boron in the skeletal framework have not been prepared, but zhang et al.
Icosahedral boranes, carboranes, and metallacarboranes are extraordinarily robust compounds with desirable properties such as thermal and redox stability, chemical inertness, low nucleophilicity, and high hydrophobicity, making them attractive for several applications such as medicine, nanomaterials, molecular electronics, energy, catalysis, environmental chemistry, and other areas. In carboranes, the b and c atoms are arranged at the vertices of the more or less regular polyhedron. Carborane acids are so strong that they protonate or react with almost every solvent. Carboranes article about carboranes by the free dictionary.
The role of homogeneous and heterogeneous carborane and metallacarborane catalysts in a variety of organic reaction types including hydrogenation, hydrosilylation, polymerization. Metallacarborane complexes, incorporating one or more metal atoms within. The medicinal chemistry of dicarbaclosododecaboranes otherwise referred to as carboranes has traditionally centered on their use in boron neutron capture therapy bnct. Title metallacarboranes and their interactions nui galway. It is found that these triad molecules can harvest both s1 and t1 excitons and display thermally activated delayed fluorescence12 through upconversion from nonradiative t 1 excitons into emissive s1 excitons in their aggregated states.
Pdf electrochemistry and photoluminescence of icosahedral. Icosahedral boranes, carboranes, and metallacarboranes are extraordinarily robust compounds with. These examples demonstrate how properly designed carborane derivatives, by virtue of their enhanced stability. Boranes, carboranes, metalloboranes, transition metal. Chyan, synthesis, radioiodination, and biodistribution of some nido and closomonocarbon carborane derivatives, nuclear medicine and biology, vol. The use of carboranes and metallacarboranes in materials science is receiving unprecedented attention. Boranes, carboranes, metalloboranes, transition metal carbonyls and other cluster formulas obey the law of skeletal numbers and their valences bipyramid one and 116 an octahedral shape 18. Carborane, any member of a class of organometallic compounds containing carbon c, boron b, and hydrogen h. Transition metal derivatives ofpolyhedral boranes and carboraneshan songdepartment of chemistrypenn state universitychem 516 presentation12012 2. New sulfur derivatives of carboranes and metallacarboranes.
The borane clusters and their relatives strictly obey the law of skeletal numbers and valences. The altmetric attention score is a quantitative measure of the attention that a research article has received online. Carboranes definition of carboranes by the free dictionary. Pdiicatalyzed synthesis of bifunctionalized carboranes. Performance tests indicated that carboranes are excellent materials for obtaining high uniform loadings of boron inhibitors in glassy carbon materials and thus reducing their rates of oxidation. Icosehedral carboranes are frequently used for preparation of high temperature resistant polymers,1,8 boroncontaining macromolecules for boron neutron capture therapy, bnct,8,9 and luminescent copolymers with a large system of conjugated electrons. A large number of metallacarboranes with vertices or more possessing very rich structural diversities have been prepared via different synthetic routes using various types of carboranyl ligands. New ligand platforms featuring boronrich clusters as. Multidentate carboranecontaining lewis acids and their. Carboranes synonyms, carboranes pronunciation, carboranes translation, english dictionary definition of carboranes. Gassorption properties of cobalt iicarboranebased coordination polymers as a function of morphology are discussed.
Structure and bonding of carboranes content writer. From nonpeptide toward noncarbon protease inhibitors. Boron neutron capture therapy bnct applications the chemistry of bnct. Other articles where metallacarborane is discussed. Metalcontaining carboranes with antitumor activity. Structure and bonding of carboranes the formulas of typical closo nido and arachnoboranes and carboranes are listed in boron e. Recent advances in the chemistry of carboranes and. Pdf icosahedral boranes, carboranes, and metallacarboranes are extraordinarily robust.
Carboranes, second edition is designed as a comprehensive source of information in a field that has experienced enormous growth in both its fundamental and applied aspects in the four decades since the publication of carboranes 1970. Inner shell electron energyloss spectroscopy of boranes and carboranes boron 1s iseels of nidopentaborane 9, 1, nido2,3 diethy. Metallacarbaboranes or metallacarboranes are a class of inorganic polyhedral clusters. Fusionner pdf combiner en ligne vos fichiers pdf gratuitement. The delivery of carboranes in the bnct of cancers patras, greece, 4th of july 20 drug discovery, delivery and patient care dddpc research hub faculty of science, engineering and computing, kingston university. Aminoalkyl carboranes are anticipated to be valuable synthons toward the synthesis of bifunctionalized carboranes. The borane fragments and clusters of nuclearity b 1 to b 12 have been derived using skeletal numbers and valences. Metallacarboranes as specific and potent inhibitors of hiv protease petr c. Electrochemistry and photoluminescence of icosahedral. Carboranes are electrondelocalized nonclassically bonded clusters composed of boron. Most of the carborane derivatives of the icosahedral c2b10 or small cage c2b4 systems are formed, by varying the groups on the cage carbons. We have looked at the reduction of phospha and arsacarboranes with sodium metal.
It is used in rocket propellants and as reducing agent, as a rubber vulcanizer, as a catalyst for olefin polymerization, as a flamespeed accelerator, and as a doping agent. Structure boranes and carboranes metallocarboranes. Recent developments in the study of carboranes hawthorne has recently demonstrated that the dianion is an opencage species by converting it to the transition metal complex, b10h10c2h2coc5h520. Any of a class of stable crystalline compounds composed of carbon, boron, and hydrogen. Multidentate carboranecontaining lewis acids and their chemistry. Pdf dendrimer and nanostructuresupported carboranes. Like many of the related boron hydrides, these clusters are polyhedra or fragments of polyhedra, and are similarly classified as closo, nido, arachno, hypho, etc. Oxidation of the products regenerates neutral phospha and. A series of new closo and nidocarborane based thioethers with exopolyhedral carbonsulfur bond 1xch2ns1,2c2b10h11 x cooh. Learn more about these metrics article views are the countercompliant sum of full text article downloads since november 2008 both pdf and html across all institutions and individuals. Inorganic chemistry3 metalcomplexes and metal clusters module.
Carboranes, third edition, by russell grimes, is the definitive resource on the subject. The concept of raw skeletal structures which directly produce the parental cluster formulas has been introduced. Carborane article about carborane by the free dictionary. However, direct cage boron derivation of these carborane derivatives has not been solved. Carboranes having more than two carbon atoms in the skeletal framework, obtained in a variety of ways, include derivatives of nidoc 3 b 3 h 7, nidoc 3 b 8 h 11. We decided to combine ec and pl of boron clusters because both processes are related in the sense. Results and discussion to create a new carboranebased mof with a large pore volume and surface area, a relatively long boronrich ligand was synthesized that consists of a central pcarborane unit and two isophthalic acid groups lh4scheme 1. Department of chemistry and biochemistry, northern illinois university, dekalb. Carborane definition of carborane by the free dictionary. These metrics are regularly updated to reflect usage leading up to the last few days. Here the authors report an iridiumcatalysed borylation ofocarboranes with.
Dendrimer and nanostructuresupported carboranes and. Airgas usa, llc and its affiliates 259 north radnorchester road suite 100 radnor, pa 19087. The c2b10h12 isomers, together with other carborane clusters and metallacarboranes see below are. Mo treatments of closo boranes and carboranes the bonding in nido and arachno carboranes methods of synthesis and interconversion reactions. Housecroft department of chemistry, university of basel, spitalstrasse 51, 4056 basel, switzerland email. Herein, the reversible conversion of catalytically infeasible ocarboranyl methylamines 1ch2nh2ocarb most popular 20182019 main group, inorganic and organometallic chemistry articles. Further, there is evidence that the use of substituted derivatives could provide. Dynamic modeling of hydrogen generation via hydrolysis of. In coordination chemistry, it is used as unique bulky ligand scaffolds. One of the b or c atoms in carboranes can be replaced by one atom of another element, such. Efforts of half a century in this research area have led to the extensive studies on the chemistry of carboranes and metallacarboranes.
Syntheses of icosahedral closodicarbadodecaborane derivatives r 2 c 2 b 10 h 10 employ alkynes as the r 2 c 2 source and decaborane b 10 h 14 to supply the b 10 unit tricarba, tetracarba, pentacarba, and hexacarba clusters. The layer of carboranes changes the geometry and stability of the material beneath. Diborane is a colorless gas with a repulsive, sweet odor. The examples described in this manuscript highlight some recent developments demonstrating how carboranes and metallacarboranes have been successfully employed as organomimetic substituents within several ligand platforms fig.
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