|
Cubane
Cubane () is a synthetic hydrocarbon compound that consists of eight carbon atoms arranged at the corners of a cube, with one hydrogen atom attached to each carbon atom. A solid crystalline substance, cubane is one of the Platonic hydrocarbons and a member of the prismanes. It was first synthesized in 1964 by Philip Eaton and Thomas Cole. Before this work, Eaton believed that cubane would be impossible to synthesize due to the "required 90 degree bond angles". The cubic shape requires the carbon atoms to adopt an unusually sharp 90° bonding angle, which would be highly strained as compared to the 109.45° angle of a tetrahedral carbon. Once formed, cubane is quite kinetically stable, due to a lack of readily available decomposition paths. It is the simplest hydrocarbon with octahedral symmetry. Having high potential energy but kinetic stability makes cubane and its derivative compounds useful for controlled energy storage. For example, octanitrocubane and heptanitrocubane have ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Octanitrocubane
Octanitrocubane (molecular formula: C8(NO2)8) is a high explosive that, like Trinitrotoluene, TNT, is shock-insensitive (not readily detonated by shock). The octanitrocubane molecule has the same chemical structure as cubane (C8H8) except that each of the eight hydrogen atoms is replaced by a nitro compound, nitro group (NO2). It is however not as powerful an explosive as once thought, as the high-density theoretical crystal structure has not been achieved. For this reason heptanitrocubane, the slightly less nitrated form is believed to have marginally better performance, despite having a worse oxygen balance. Octanitrocubane is thought to have 20–25% greater performance than HMX (octogen). This increase in power is due to its highly expansive breakdown into CO2 and N2, as well as to the presence of strained chemical bonds in the molecule which have stored potential energy. In addition, it produces no water vapor upon combustion, making it less visible, and both the chemical i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Octanitrocubane
Octanitrocubane (molecular formula: C8(NO2)8) is a high explosive that, like Trinitrotoluene, TNT, is shock-insensitive (not readily detonated by shock). The octanitrocubane molecule has the same chemical structure as cubane (C8H8) except that each of the eight hydrogen atoms is replaced by a nitro compound, nitro group (NO2). It is however not as powerful an explosive as once thought, as the high-density theoretical crystal structure has not been achieved. For this reason heptanitrocubane, the slightly less nitrated form is believed to have marginally better performance, despite having a worse oxygen balance. Octanitrocubane is thought to have 20–25% greater performance than HMX (octogen). This increase in power is due to its highly expansive breakdown into CO2 and N2, as well as to the presence of strained chemical bonds in the molecule which have stored potential energy. In addition, it produces no water vapor upon combustion, making it less visible, and both the chemical i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heptanitrocubane
Heptanitrocubane is an experimental high explosive based on the cubic eight-carbon cubane molecule and closely related to octanitrocubane. Seven of the eight hydrogen atoms at the corners of the cubane molecule are replaced by nitro groups, giving the final molecular formula . As with octanitrocubane, not enough heptanitrocubane has been synthesized to perform detailed tests on its stability and energy. It is hypothesized to have slightly better performance than explosives such as HMX, the current high-energy standard explosive, based on chemical energy analysis. While in theory not as energetic as octanitrocubane's theoretical maximum density, the HNC that has been synthesized so far is a more effective explosive than any ONC that has been produced, due to more efficient crystal packing and hence higher density. Heptanitrocubane was first synthesized by the same team who synthesized octanitrocubane, Philip Eaton and Mao-Xi Zhang at the University of Chicago The Univers ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Octafluorocubane
Octafluorocubane or perfluorocubane is an organofluorine compound with the formula , consisting of eight carbon atoms joined into a cube, with a fluorine bonded to each carbon corner. It is a colorless, sublimable solid at room temperature. It has been of longstanding theoretical interest, but was not synthesised until 2022, when it was prepared in several steps from a cubane carboxylic ester beginning with its heptafluorination. According to X-ray crystallography, the C-C distances (1.572 Å) in octafluorocubane are identical in length to those in the parent cubane. Octafluorocubane has attracted interest from theorists because of its unusual electronic structure, which is indicated by its susceptibility to undergo reduction to a detectable anion , with the free electron trapped inside of the cube. The compound was voted "favorite molecule of 2022" by readers of ''Chemical & Engineering News ''Chemical & Engineering News'' (''C&EN'') is a weekly news magazine published by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Octaazacubane
Octaazacubane is a hypothetical explosive allotrope of nitrogen with formula N8, whose molecules have eight atoms arranged into a cube. (By comparison, nitrogen usually occurs as the diatomic molecule N2.) It can be regarded as a cubane-type cluster, where all eight corners are nitrogen atoms bonded along the edges. It is predicted to be a metastable molecule, in which despite the thermodynamic instability caused by bond strain, and the high energy of the N–N single bonds, the molecule remains kinetically stable for reasons of orbital symmetry. Explosive and fuel Octaazacubane is predicted to have an energy density (assuming decomposition into N2) of 22.9 MJ/ kg, which is over 5 times the standard value of TNT. It has therefore been proposed (along with other exotic nitrogen allotropes) as an explosive, and as a component of high performance rocket fuel. Its velocity of detonation is predicted to be 15,000 m/s, much (48.5%) more than octanitrocubane, the faste ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prismane C8
Carbon is capable of forming many allotropes (structurally different forms of the same element) due to its valency. Well-known forms of carbon include diamond and graphite. In recent decades, many more allotropes have been discovered and researched, including ball shapes such as buckminsterfullerene and sheets such as graphene. Larger-scale structures of carbon include carbon nano tube, nanotubes, nanobuds and nanoribbons. Other unusual forms of carbon exist at very high temperatures or extreme pressures. Around 500 hypothetical 3‑periodic allotropes of carbon are known at the present time, according to the Samara Carbon Allotrope Database (SACADA). Diamond Diamond is a well-known allotrope of carbon. The hardness, extremely high refractive index, and high dispersion of light make diamond useful for industrial applications and for jewelry. Diamond is the hardest known natural mineral. This makes it an excellent abrasive and makes it hold polish and luster extreme ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cuneane
Cuneane (C8H8, pentacyclo .3.0.02,4.03,7.06,8ctane) is a saturated hydrocarbon. Its name is derived from the Latin ''cuneus'', meaning a wedge. Cuneane may be produced from cubane by metal-ion-catalyzed σ-bond rearrangement. Similar reactions are known for homocubane (C9H10) and bishomocubane (C10H12). : Molecular geometry The carbon atoms in the cuneane molecule form a hexahedron with point group C2v. The cuneane molecule has three groups of equivalent carbon atoms (A, B, C), which have also been confirmed by NMR. The molecular graph of the carbon skeleton of cuneane is a regular graph with non-equivalent groups of vertices, and so it is a very important test object for different algorithms of mathematical chemistry. : Derivatives Some cuneane derivatives have liquid crystal Liquid crystal (LC) is a state of matter whose properties are between those of conventional liquids and those of solid crystals. For example, a liquid crystal may flow like a liquid, but it ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Philip Eaton
Philip E. Eaton (born 1936) is a Professor Emeritus of Chemistry at the University of Chicago. He and his fellow researchers were the first to synthesize the "impossible" cubane molecule in 1964.P. Eaton and T. W. Cole, The Cubane System, J. Am. Chem. Soc., 86 (1964) 962.doi:10.1021/ja01059a072/ref>P. Eaton and T. W. Cole, Cubane, J. Am. Chem. Soc., 86 (1964) 3157doi:10.1021/ja01069a041/ref> Working with Mao-Xi Zhang he is reported as having been the first to make octanitrocubane (their paper was published in the year 2003) Because of its eight nitro groups and highly strained C-C bonds - octanitrocubane is a very powerful high explosive. Early years Philip E. Eaton was born in 1936 in Brooklyn, New York. When Eaton was seven his family relocated to Budd Lake, New Jersey. Here he began attending Roxbury Grammar School and later Roxbury High School. It was during these high school years that he began to find his passion for science. It was the support of his parents and teachers ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Platonic Hydrocarbon
In organic chemistry, a Platonic hydrocarbon is a hydrocarbon (molecule) whose structure matches one of the five Platonic solids, with carbon atoms replacing its vertices, carbon–carbon bonds replacing its edges, and hydrogen atoms as needed. Not all Platonic solids have molecular hydrocarbon counterparts; those that do are the tetrahedron (tetrahedrane), the cube (cubane), and the dodecahedron (dodecahedrane). Tetrahedrane Tetrahedrane (C4H4) is a hypothetical compound. It has not yet been synthesized without substituents, but it is predicted to be kinetically stable in spite of its angle strain. Some stable derivatives, including tetra( ''tert''-butyl)tetrahedrane (a hydrocarbon) and tetra(trimethylsilyl)tetrahedrane, have been produced. Cubane Cubane (C8H8) has been synthesized. Although it has high angle strain, cubane is kinetically stable, due to a lack of readily available decomposition paths. Octahedrane Angle strain would make an octahedron highly unstable due to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prismanes
The prismanes are a class of hydrocarbon compounds consisting of prism-like polyhedra of various numbers of sides on the polygonal base. Chemically, it is a series of fused cyclobutane rings (a ladderane, with all-cis/all- syn geometry) that wraps around to join its ends and form a band, with cycloalkane edges. Their chemical formula is (C2H2)n, where ''n'' is the number of cyclobutane sides (the size of the cycloalkane base), and that number also forms the basis for a system of nomenclature within this class. The first few chemicals in this class are: Triprismane, tetraprismane, and pentaprismane have been synthesized and studied experimentally, and many higher members of the series have been studied using computer models. The first several members do indeed have the geometry of a regular prism, with flat ''n''-gon bases. As ''n'' becomes increasingly large, however, modeling experiments find that highly symmetric geometry is no longer stable, and the molecule distorts into les ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dodecahedrane
Dodecahedrane is a chemical compound, a hydrocarbon with formula , whose carbon atoms are arranged as the vertices (corners) of a regular dodecahedron. Each carbon is bound to three neighbouring carbon atoms and to a hydrogen atom. This compound is one of the three possible Platonic hydrocarbons, the other two being cubane and tetrahedrane. Dodecahedrane does not occur in nature and has no significant uses. It was synthesized by Leo Paquette in 1982, primarily for the "aesthetically pleasing symmetry of the dodecahedral framework". For many years, dodecahedrane was the simplest real carbon-based molecule with full icosahedral symmetry. Buckminsterfullerene (), discovered in 1985, also has the same symmetry, but has three times as many carbons and 50% more atoms overall. The synthesis of the C20 fullerene in 2000, from brominated dodecahedrane, may have demoted to second place. Structure The angle between the C-C bonds in each carbon atom is 108°, which is the angle between a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyclopentenone To 2-bromocyclopentadienone
2-Cyclopentenone is a ketone with chemical formula and CAS number 930-30-3. It is structurally similar to cyclopentanone, with the additional feature of enone, α-β unsaturation in the ring system. 2-Cyclopentenone contains two functional groups, a ketone and an alkene. It is a colorless liquid. The term cyclopentenone may also refer to a structural motif wherein the cyclopentenone moiety (chemistry), moiety is a subunit of a larger molecule. Cyclopentenones are found in a large number of natural products, including jasmone, the aflatoxins, and several prostaglandins. Synthesis 2-Cyclopentenones can be synthesized in a number of ways. One of the routes involves elimination of α-alkyl bromide, bromo-cyclopentanone using lithium carbonate and Claisen condensation-decarboxylation-isomerization cascades of unsaturated diesters as shown below. The acid-catalyzed dehydration of cyclopentanediols affords cyclopentenone. As a functional group, the synthesis of 2-cyclopentenones is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
