Request PDF on ResearchGate | Carboranes and Metallacarboranes | IntroductionCarborane Structures and Skeletal Electron NumbersLocalized Bond . Most of the carborane derivatives of the icosahedral (C2B10) or small cage ( C2B4) systems are formed, by varying the groups on the cage carbons. This is. The general formula of carboranes is represented by C2BnHn + 2, in which n is an derivatives called metallacarboranes, some of which show catalytic activity.
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Greenwood, and their colleagues. Our editors will review what you’ve submitted, and if it meets our criteria, we’ll add it to the article. Most of the carborane derivatives of the icosahedral C2B10 or small cage C2B4 systems are formed, by varying metallacarborsnes groups on the cage carbons.
Carboranes from the Reaction of Decaborane with Acetylenic Compounds”. Chemistry — A European Journal. The mettallacarboranes commonly encountered carborane jetallacarboranes is icosahedral dicarbaborane C 2 B 10 H Base-induced degradation of carboranes give anionic nido derivatives that are used as ligands.
Carboranes are a notable example of heteroboranes. In addition, the nomenclature of carboranes employs the same structural prefixes closo – arachno – etc. The first three carboranes—trigonal bipyramidal 1,5-C 2 B 3 H 5 ; the 1,2- and 1,6- isomers of octahedral C 2 B 4 H 6 ; and pentagonal pyramidal 2,4-C 2 B 5 H 7 —that were produced in the s were generated in low yield by the reaction of pentaborane 9 with acetylene in a silent electric discharge.
The metallacarborabes applications of carboranes have been explored. Metalany of a class of substances characterized by high electrical and thermal conductivity as well as by malleability, ductility, and high reflectivity of light.
This page was last edited on 28 Novemberat At the bottom of the article, feel free to list any sources that support your changes, so that we can fully understand their context. We prepared the first carborane derivitive isopropenyl carborane, which I purified for analysis. Please note that metallzcarboranes editors may make some formatting changes or correct spelling or grammatical errors, and may also contact you if any clarifications are needed.
In the late ‘s and early ‘s I was working at Reaction Motors doing classified contract work on decaborane derivitaives for the Air force. Since then, many thousands of carboranes have been prepared, and they have been combined with transition metals to yield derivatives called metallacarboranes, some of which show catalytic activity.
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I then prepared diacetoxymethyl carborane and hydrolyzed it to dihydroxymethyl carborane. Their most significant structural feature is the covalent bonding of carbon simultaneously to five or six other atoms. A carborane is a cluster composed of boroncarbon and hydrogen atoms.
Retrieved from ” https: Thank You for Your Contribution! Your contribution may be further edited by our staff, and its publication is subject to our final approval. Its molecular structure resembles an icosahedron with the 10 boron atoms and two adjacent carbon atoms forming the apices.
The icosahedral closo -carboranes are particularly stable. There was a problem with your submission. Guidelines Upcoming Special Issues. This is usually accomplished in the original carborane synthesis by reacting substituted acetylenes with either the B10H14 or B5H9 precursors. After two to Three years this work was declassified and allowed to be published. In other projects Wikimedia Commons. We welcome suggested improvements to any of our articles.
Carboranes And Metallacarboranes: Advances And New Perspectives |
These dilithiated compounds react with a variety of electrophiles, e. Hydrogen Ha colourless, odourless, tasteless, flammable gaseous substance that is the simplest member of the family of chemical elements. Not only has their chemistry been the most extensively studied of all carboranes, but their discovery ushered in the rapid development of the field.
Depending on the location of the carbon atoms in the boron cage, dicarbaboranes are classified into three isomers: Boraneany of a homologous series of inorganic compounds of boron and hydrogen or their derivatives.
We sent bi-weekly reports to the Air Force which circulated them to other contractors doing similar research among which was Olin Matheson. For example, the reaction of pentaborane 9 with acetylene affords all three isomers:. Carboraneany member of a class of organometallic compounds containing carbon Cboron Band hydrogen H. If you prefer to suggest your own revision of the article, you can go to edit mode requires login.
A meeting was held with the editors of Inorganic Chemistry with the aim of arranging priorities. Please try again later. Dicarbollide complexes have been evaluated for many applications but few have been commercialized. Geometrical isomers of carbaboranes may exist, necessitating the use of the numerical prefixes in a compound’s name.
This derivative has been considered for a wide range of applications from heat-resistant polymers to medical applications. These reactions led directly to the carbons adjacent carboranes in which the carbon atoms occupy adjacent positions in the cage.
Some complexes exhibit catalytic properties,  ion-exchange materials for radioactive waste management. Similarly, the carbaborane closo 1,6-C 2 B 4 H metallacaeboranes is isoelectronic and isostructural with the closo – borane anion B 6 H 6 2-whose core is a regular octahedron of boron atoms.
Di carbaboranes can be prepared from boron hydride clusters with an alkyne as the source of the two carbon centers. The Case of Carboranyllithium”. Carboranes are generally prepared by reaction of acetylene or acetylene derivatives with boron hydrides. The discovery of these compounds is complicated.