Carboranes, third edition, by russell grimes, is the definitive resource on the subject. Full text full text is available as a scanned copy of the original print version. Oxidation of the products regenerates neutral phospha. Chyan, synthesis, radioiodination, and biodistribution of some nido and closomonocarbon carborane derivatives, nuclear medicine and biology, vol. The editors of encyclopaedia britannica this article was most recently revised and updated by adam augustyn, managing editor, reference content. Inorganic chemistry3 metalcomplexes and metal clusters module. Sometimes the term carborane is used as a synonym for closo1,2c 2 b 10 h 12, commonly referred to as orthocarborane. Rutheniumcatalyzed metathesis reactions of ortho and. The regioselectivity and ease of derivatization of carboranes allows for facile syntheses of a wide variety of novel structures. Tjarks, carborane clusters in computational drug design. Like many of the related boranes, these clusters are polyhedra and are similarly classified as closo, nido, arachno, hypho, etc. Boranes, carboranes, metalloboranes, transition metal.
Carboranes are primarily formed by the interaction of acetylene derivatives with the corresponding boranes. Polyhedral boranes and carboranes as versatile species. Carborane definition of carborane by the free dictionary. Carbohydrates, all coming from the process of photosynthesis, represent the major part of organic substance on earth, are the most abundant organic components in the major part of fruits, vegetables.
Based on the work presented at a trailblazing symposium held at the loker hydrocarbon research. Orthocarborane is the organoboron compound with the formula c 2 b 10 h 12. Boranes are a large group of group hydride compounds that have the generic formula bxhy. Look up wades rules which describe the bonding in boron hydride clusters. Aquifers ru ru a stratum of permeable rock, sand, or gravel that will yield a significant quantity of water. In particular, they have provided many interesting examples for testing theories on chemical bonding and structure. You cant really think of the bonding in clusters like this as traditional lewis bonds. The borane, carborane, carbocation continuum explores the emerging understanding of the similarities of properties and behavior shared by these electrondeficient species. A series of novel carboranes bearing electron withdrawing fluorinated aryl groups is. In their properties the borothallated carboranes differ sharply from the aryl analogs but resemble the cthallated carboranes. The carborane b 10 c 2 h 12 is used in the preparation of different types of polymers used in solid rocket fuels and as a thermostable coating. Carboranes represent a potentially rich but underutilized class of inorganic and catabolisminert pharmacophores. The altmetric attention score is a quantitative measure of the attention that a research article has received.
Get a printable copy pdf file of the complete article 1. Carboranes are therefore capable of undergoing various transformations related to the substitution of the h atoms located at the c or b atom. The layer of carboranes changes the geometry and stability of the material beneath. Iridiuminduced regioselective b hand c cactivations at. The borane, carborane, carbocation continuum physical. Carborane definition of carborane by merriamwebster. The altmetric attention score is a quantitative measure of the attention that a research article has received online. Links to pubmed are also available for selected references.
Framework rearrangement in boranes and carboranes science. It typically breaks down in the animal body to release energy. Further, there is evidence that the use of substituted derivatives could provide more complete and thorough forms of protection. Polyhedral boranes and carboranes have acquired their popularity for constructing meso and nanosize structures for an array of applications from pharmaceuticals to material science. Carbohydrates, together with lipids, proteins and nucleic acids, are one of the four major classes of biologically essential organic molecules found in all living organisms. Any of a class of stable crystalline compounds composed of carbon, boron, and hydrogen. Carboranes are of interest because of their nonclassical bonding, their relatively high thermal stability, and their ability, when containing the 10 b isotope, to capture neutrons efficiently. Carboranyl derivatives of thallium with a btl bond were obtained by the direct thallation of substituted carboranes. The steric bulk, rigidity, and ease of b and cderivatization and lack of. A carborane is a cluster composed of boron and carbon atoms.
Examples of nido and arachno carboranes include 2,3c 2 b 4 h 8 and 1,3c 2 b 7 h, respectively. The three common isomers are ocarborane, mcarborane and pcarborane 1the structure could be polyhedral or open cage. 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. In coordination chemistry, it is used as unique bulky ligand scaffolds. The class of ternary compounds called carboranes containing the elements carbon, boron and hydrogen have played a prominent role in many areas of fundamental chemical research. One interesting borane form is the dodecaborane dianion, b12h122. Geometrical isomers of carboranes can exist, necessitating the use of the numerical prefixes in a compounds name. Preparation and properties of nidocarboranespecific. Structure and bonding of carboranes content writer. Classification of carbohydrates with types, structure. 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. Ru ru arbor project aquiculture approximations 20000412 inis. Accordingly, the first vertex carborane l,2c 6 h 4 ch 2 25phl,2c 2 b 11 h 10 was prepared by the welch group in 6% yield from the reaction of 7,8c 6 h 4 ch 2 27,8c 2 b 10 h 10na 2 with phbcl 2.
The stabilisation of reduced carboranes semantic scholar. The ratio of oxygen and hydrogen in carbohydrates is the same as in water i. General description electron deficient boron cage compounds with one or more carbon atoms as a ligand in the borane framework. Polyhedral boranes wades rules heteroboranes molecular orbital picture examples understanding wades rules classify the following polyhedral boranes according to their valence electron count. Therefore to obtain a cc bond, or in other words to join both molecules. We have looked at the reduction of phospha and arsacarboranes with sodium metal.
Carborane, any member of a class of organometallic compounds containing carbon c, boron b, and hydrogen h. In all but a few cases, this definition clearly separates the carboranes from conventional organoboranes whose hydrocarbonlike structures can be described entirely in terms of 2c2e bonds. Borontransition metal bond organoelement chemistry. Syntheses of odialkenylcarboranes 1,2ch 2chch 2 21,2c 2b 10 h 10 1. Synthesis and evaluation of transthyretin amyloidosis. Box 4833, hochland park, windhoek, namibia abstract the borane fragments and clusters of nuclearity b 1 to b. Carboranes article about carboranes by the free dictionary. It is a group of organic compounds occurring in living tissues and foods in the form of starch, cellulose, and sugars. Carborane article about carborane by the free dictionary. Carboranes definition of carboranes by the free dictionary. Phosphonates and phosphonium salts derivatives of carboranes. 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.
These metrics are regularly updated to reflect usage leading up to the last few days. This derivative has been considered for a wide range of applications from heatresistant polymers to medical applications. Pdf on oct 3, 2011, barada dash and others published carborane clusters. Structure and bonding of carboranes the formulas of typical closo nido and arachnoboranes and carboranes are listed in boron e. These threedimensional boranes range from 4 to 22 boron atom per molecules with delocalized bonding analogous to aromatic compounds. A comparative examination of electrondeficient species from leading researchers in the field. 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.