chembox verifiedrevid 443548678 ImageFile Cycloheptatriene.png ImageSize 120px IUPACName 1,3,5 cycloheptatriene OtherNames CHT Section1 Chembox Identifiers ChemSpiderID Ref chemspidercite correct chemspider ChemSpiderID 10534 InChI 1 C7H8 c1 2 4 6 7 5 3 1 h1 6H,7H2 InChIKey CHVJITGCYZJHLR UHFFFAOYAI StdInChI Ref stdinchicite correct chemspider StdInChI 1S C7H8 c1 2 4 6 7 5 3 1 h1 6H,7H2 StdInChIKey Ref stdinchicite correct chemspider StdInChIKey CHVJITGCYZJHLR UHFFFAOYSA N CASNo Ref cascite correct CAS CASNo 544 25 2 ChEBI Ref ebicite correct EBI ChEBI 37519 SMILES C1 C C C C C C1 PubChem Section2 Chembox Properties C 7 H 8 Appearance Density 0.888 g mL at 25 C MeltingPtC 80 BoilingPtC 116 Solubility Insoluble in water Section3 Chembox Hazards MainHazards FlashPt Autoignition RPhrases R10 R11 R21 R23 24 25 R36 37 38 SPhrases S9 S16 S23 S28 A S33 S36 37 S45 Cycloheptatriene CHT is an organic compound with the chemical formula formula C sub 7 sub H sub 8 sub . This colourless liquid has been of recurring theoretical interest in organic chemistry . It is a ligand in organometallic chemistry and as a building block in organic synthesis . Cycloheptatriene is not aromatic , as reflected by the nonplanarity of the methylene CH sub 2 sub group with respect to the other atoms. Synthesis Albert Ladenburg first generated cycloheptatriene in 1881 by the decomposition of tropine . ref cite journal ... issue 2 pages 204 265 year 1901 doi 10.1002 jlac.19013170206 ref Cycloheptatriene can be obtained ... of cyclohexene and dichlorocarbene . ref cite journal author H.E. Winberg title Synthesis of Cycloheptatriene ... jo01084a635 ref A related classic synthesis for a cycloheptatriene derivatives, the Buchner ring ... ring expansion to the cycloheptatriene carboxylic acid ethyl ester. ref Buchner, et al., Ber., 18, 2377 ... cycloheptatriene cation, also called the tropylium ion. A practical route to this cation employs ... and cycloheptatriene are used as a Spin triplet triplet quencher for rhodamine 6G dye laser ... more details
DISPLAYTITLE C sub 7 sub H sub 8 sub The molecular formula C sub 7 sub H sub 8 sub may refer to Cycloheptatriene Isotoluene s Norbornadiene Quadricyclane Toluene MolFormDisambig el C7H8 fr C7H8 nl C7H8 ... more details
CHT or ChT may refer to TOCright Science and technology Cylinder Head Temperature, an Aircraft engine controls aircraft engine control sensor Collection, Holding and Transfer, naval ships system of sewers, see USS George H.W. Bush CVN 77 Cycloheptatriene , an organic chemical compound Medicine and biology Certified Hyperbaric Technologist, a certification offered by the National Board of Diving and Hyperbaric Medical Technology Certified hand therapist Choline transporter ChT , a protein Places Chatham Islands Tuuta Airport , in New Zealand, IATA code Chittagong Hill Tracts , in Bangladesh Transport Cross Harbour Tunnel , in Hong Kong Other Chunghwa Telecom disambig de CHT fr CHT it CHT ... more details
Unreferenced stub auto yes date December 2009 Chembox verifiedrevid 424725903 ImageFile Chemical structure of heptalene.png ImageSize 150px ImageName Skeletal formula ImageFile1 Heptalene 3D balls.png ImageSize1 170 ImageName1 Ball and stick model IUPACName Heptalene OtherNames Section1 Chembox Identifiers CASNo Ref cascite correct ?? CASNo 257 24 9 PubChem 5460725 SMILES C1 CC C2C CC CC C2C C1 Section2 Chembox Properties C 12 H 10 Appearance Density MeltingPt BoilingPt Solubility Section3 Chembox Hazards MainHazards FlashPt Autoignition Heptalene is a polycyclic hydrocarbon with chemical formula C sub 12 sub H sub 10 sub , composed of two fused cycloheptatriene rings. Hydrocarbon stub Category Heptalenes nl Heptaleen ... more details
to benzene using both thermal and photochemical pathways in the synthesis of cycloheptatriene derivatives ... in increased selectivity of cycloheptatriene derivatives. In the 1980s it was found that dirhodium ... ref Preparation Preparation of ethyl diazoacetate Buchner s first synthesis of cycloheptatriene derivatives ... , thermally allowed process. File Pericyclic.svg center 400px ring opening The norcaradiene cycloheptatriene ... on the side of the cycloheptatriene. The equilibrium may be shifted toward the norcaradiene by destabilization of the cycloheptatriene by bulky substitution large sterically hindered groups i. e. t butyl ... electron withdrawing group s EWG favor the cycloheptatriene. File EDGEWG.svg center 400px equilibrium position The tautomerism of the norcaradiene and cycloheptatriene can be understood based on the Walsh ... cycloheptatriene isomers. Noels et al. used Rh II catalysts for carbene generation under mild reaction conditions room temperature to obtain regioselectively the kinetic non conjugated cycloheptatriene ... 78 pages 5448 doi 10.1021 ja01601a080 ref File Conj nonconj.svg center 500px cycloheptatriene derivatives See also electrocyclic reaction Cycloheptatriene Carbene References Reflist 2 Category Organic ... more details
Chembox ImageFile Tropylium tetrafluoroborate.svg ImageSize 150px ImageAlt IUPACName PIN OtherNames Section1 Chembox Identifiers CASNo 27081 10 3 ChemSpiderID 134784 PubChem SMILES F B F F F.c1cccccc1 Section2 Chembox Properties C 7 H 7 B 1 F 4 Appearance Density MeltingPt BoilingPt Solubility Section3 Chembox Hazards MainHazards FlashPt Autoignition Tropylium tetrafluoroborate is an organic compound containing the tropylium cation and the non coordinating tetrafluoroborate counteranion. It is a stable salt which is commercially available. This compound may be prepared by the reaction of cycloheptatriene with phosphorus trichloride , followed by tetrafluoroboric acid . ref cite encyclopedia last1 Kane first1 John L. last2 Danheiser first2 Rick L. title Encyclopedia of Reagents for Organic Synthesis encyclopedia Encyclopedia of Reagents for Organic Synthesis year 2001 doi 10.1002 047084289X.rt429 chapter Tropylium Tetrafluoroborate isbn 0471936235 ref See also Trityl chloride References references Category Tetrafluoroborates Category Carbocations ... more details
In organic chemistry , the tropylium ion is an aromatic species with a formula of C sub 7 sub H sub 7 sub sup sup . ref GoldBookRef title molecule file M04002 ref Its name derives from the molecule tropine itself named for the molecule atropine . Salts of the tropylium cation can be stable, e.g. tropylium tetrafluoroborate . It can be made from cycloheptatriene tropylidene and bromine or phosphorus pentachloride ref Tropylium tetrafluorate Organic Syntheses, Coll. Vol. 5, p.1138 1973 Vol. 43, p.101 1963 . http orgsyn.org orgsyn pdfs CV5P1138.pdf link ref It is a heptagon al, planar, cyclic ion as well, it has 6 electrons 4n 2, where n 1 , which fulfills H ckel s rule of aromaticity. It can coordinate as a ligand to metal atoms . center align center class wikitable center Image Tropylium ion 2D skeletal.png 130px center center Image Tropylium ion 3D balls.png 150px center center Image Tropylium ion 3D vdW.png 150px center center skeletal formula center center ball and stick model center center space filling model center center The structure shown is a composite of seven resonance contributor s in which each carbon carries part of the positive charge. In 1891 G. Merling obtained a water soluble salt from a reaction of cycloheptatriene and bromine ref Merling, G. 1891 , Ueber Tropin . Berichte der deutschen chemischen Gesellschaft, 24 3108 3126. doi 10.1002 cber.189102402151 ref . The structure was elucidated by William von Eggers Doering von Eggers Doering and Knox in 1954 ref The Cycloheptatrienylium Tropylium Ion W. Von E.Doering, L. H. Knox J. Am. Chem. Soc., 1954, 76 12 , pp 3203 3206 DOI 10.1021 ja01641a027 ref ref Aromaticity as a Cornerstone of Heterocyclic Chemistry Alexandru T. Balaban, Daniela C. Oniciu, Alan R. Katritzky Chem. Rev., 2004, 104 5 , pp 2777 2812 DOI 10.1021 cr0306790 ref Mass spectrometry The tropylium ion is frequently encountered in mass spectrometry in the form of a signal at m z 91 and is used in mass spectrum analysis . This ... more details
from fusion of cyclopentadiene and cycloheptatriene rings. Like naphthalene and cyclodecapentaene ... ref The alternative approach from cycloheptatriene has long been known, one illustrative method ... procedure. step 1 cycloheptatriene 2 2 cycloaddition with dichloro ketene step 2 diazomethane insertion ... more details
Image Cycloheptatriene Norcaradiene Rearrangement.png right 300px Example of a pericyclic reaction the Cyclohexatriene norcaradiene rearrangement In organic chemistry , a pericyclic reaction is a type of organic reaction wherein the transition state of the molecule has a cyclic geometry, and the reaction progresses in a concerted reaction concerted fashion. Pericyclic reactions are usually rearrangement reaction s. The major classes of pericyclic reactions are class wikitable rowspan 2 Name colspan 2 Bond changes Sigma Pi Electrocyclic reaction 1 1 Cycloaddition 2 2 Sigmatropic reaction 0 0 Group transfer reaction 1 1 Cheletropic reaction 2 2 Dyotropic reaction 0 0 In general, these are considered to be Chemical equilibrium equilibrium processes , although it is possible to push the reaction in one direction by designing a reaction by which the product is at a significantly lower energy level this is due to a unimolecular interpretation of Le Chatelier s principle . Pericyclic reactions often have related stepwise Radical chemistry radical processes associated with them. Some pericyclic reactions, such as the 2 2 cycloaddition, are controversial because their mechanism is not definitively known to be concerted or may depend on the reactive system . Pericyclic reactions also often have metal catalyzed analogs, although usually these are also not technically pericyclic, since they proceed via metal stabilized intermediates, and therefore are not concerted. A large photoinduced hydrogen sigmatropic shift was utilized in a corrin synthesis performed by Albert Eschenmoser containing a 16 system. ref A New Type of Corrin Synthesis. Yasuji Yamada, D. Miljkovic, P. Wehrli, B. Golding, P. Loliger, R. Keese, K. Miiller, and A. Eschenmoser. http www3.interscience.wiley.com cgi bin fulltext 106576485 PDFSTART Angew. Chem. Int. Edit. 1969 , 8 5 ,343 348. ref Due to the principle of microscopic reversibility , there is a parallel set of retro pericyclic reactions, which perform the reverse ... more details
See also List of UN Numbers UN 2601 to UN 2700 class wikitable width 140px UN Number Class Proper Shipping Name UN 2601 2 Cyclobutane UN 2602 2 Dichlorodifluoromethane and 1,1 Difluoroethane difluoroethane azeotropic mixture or Refrigerant gas R 500 with approximately 74 percent dichlorodifluoromethane UN 2603 3 Cycloheptatriene UN 2604 8 Boron trifluoride diethyl ether ate UN 2605 3 Methoxymethyl isocyanate UN 2606 6.1 Methyl orthosilicate UN 2607 3 Acrolein dimer , stabilized UN 2608 3 Nitropropane s UN 2609 6.1 Triallyl borate UN 2610 3 Triallylamine UN 2611 6.1 Propylene chlorohydrin UN 2612 3 Methyl propyl ether UN 2614 3 Methallyl alcohol UN 2615 3 Ethyl propyl ether UN 2616 3 Triisopropyl borate UN 2617 3 Methylcyclohexanol s, flammable UN 2618 3 Vinyltoluene s, inhibited UN 2619 8 Benzyldimethylamine UN 2620 3 Amyl butyrate s UN 2621 3 Acetyl methyl carbinol UN 2622 3 Glycidaldehyde UN 2623 4.1 Firelighter s, solid with flammable liquid UN 2624 4.3 Magnesium silicide UN 2626 5.1 Chloric acid aqueous solution, with not more than 10 percent chloric acid UN 2627 5.1 Nitrite s, inorganic, n.o.s. UN 2628 6.1 Potassium fluoroacetate UN 2629 6.1 Sodium fluoroacetate UN 2630 6.1 Selenate or Selenite ion Selenite UN 2642 6.1 Fluoroacetic acid UN 2643 6.1 Methyl bromoacetate UN 2644 6.1 Methyl iodide UN 2645 6.1 Phenacyl bromide UN 2646 6.1 Hexachlorocyclopentadiene UN 2647 6.1 Malononitrile UN 2648 6.1 1,2 Dibromobutan 3 one UN 2649 6.1 1,3 Dichloroacetone UN 2650 6.1 1,1 Dichloro 1 nitroethane UN 2651 6.1 4,4 Diaminodiphenyl methane UN 2653 6.1 Benzyl iodide UN 2655 6.1 Potassium fluorosilicate UN 2656 6.1 Quinoline UN 2657 6.1 Selenium disulfide UN 2659 6.1 Sodium chloroacetate UN 2660 6.1 Nitrotoluidine s mono UN 2661 6.1 Hexachloroacetone UN 2662 6.1 Hydroquinone UN 2664 6.1 Dibromomethane UN 2667 6.1 Butyltoluene s UN 2668 6.1 Chloroacetonitrile UN 2669 6.1 Chlorocresol disambiguation Chlorocresol s, liquid or Chlorocresols, solid UN 2670 8 Cyanuric chloride UN ... more details
Orphan date July 2011 A tuck in complex is an organometallic molecule where a methyl group on a methyl substituted coordinated ring ligand bonds to the central metal. The term tuck in is coined from the fact that this reaction cause the ligand to bend back towards the metal as if it were being tucked in. During the process of tucking in, the methyl group loses a C H bond that is replaced with a C M bond. In cases where molecules undergo a tuck in , hydrogen gas often is produced. In many other tuck in reactions the ring methyl reacts displacing another methyl bound to the metal liberating methane. When first discovered a tuck in was thought to be a form of organic reaction called Directed ortho metalation ortho metallation . ref name Chem001Harder Harder, S. Intramolecular C H activation in alkaline earth metal complexes 42 Angew. Chem. Int. Ed. 2003 3430 3434. anie.200351055 ref They came to be known as cyclometallations instead because of the new metal containing ring that was formed in the process. This process readily happens at d sup 0 sup centers because it involves no intermediate where the metal uses non valence electrons. The most common cases of tucked in complexes involve a pentamethylcyclopentadienyl ring Cp . The reaction is not limited to Cp , as many other aromatic rings also share the same properties, such as benzene or cycloheptatriene , with methyl substitution. The first use of the term tucked in in the scientific literature was by Cloke et al. . ref name Chem001Geoffrey Cloke, G. N. Green, J. C. Green, M. H. and Morley, C. P. Metal Atom Synthesis and Photochemistry of Bis q pentamethylcyclopentadienyl tungsten Dihydride J. Chem. Soc, Chem. Communication 1985 3430 3434. doi 10.1039 C39850000945 ref Synthesis Forming a tucked in complex is a relatively simple reaction. Because it is an intramolecular reaction intramolecular rearrangement it requires no external chemicals or catalysts. With the addition of heat or light, an CH on a ring methyl i ... more details
Orphan date February 2011 correct title reason bracket 6 4 cycloaddition 6 4 Cycloaddition is a chemical reaction between a six atom pi system and a four atom pi system, leading to a ten membered ring. Because this is a higher order cycloaddition, issues of periselectivity arise in addition to the usual concerns about regio and stereoselectivity. Six atom pi systems that have been employed in the reaction include tropone and tropone derivatives, fulvene s, and cycloheptatriene cobalt complexes. ref Rigby, J. H. Org. React. 1997 , 49 , 331. doi http dx.doi.org 10.1002 0471264180.or049.02 10.1002 0471264180.or049.02 ref Introduction 6 4 Cycloaddition is a thermally allowed, higher order cycloaddition process leading to ten membered rings. Although most linear, acyclic trienes do not give 6 4 products selectively, cyclic trienes give high yields of 6 4 products in many cases. Both cycloheptatrienes and fulvenes can be employed in this reaction, and electron deficient tropone s in particular work well. The pericyclic and transition metal mediated versions of the reaction are stereocomplementary the former gives exo products, and the latter endo products, with essentially complete selectivity in nearly all cases. The possibility of building complex carbocyclic frameworks efficiently has made this reaction particularly attractive synthetically. ref Rigby, J. H. in Comprehensive Organic Synthesis , Trost, B. M. Fleming, I., Eds., Vol. 5 , Pergamon, Oxford, 1991, pp. 617 643. ref span style float right padding right 50px padding top 30px 1 span center File 64Gen.png center Mechanism and Stereochemistry Metal free reaction The metal free version of the 6 4 cycloaddition takes place through a concerted, pericyclic process. The frontier molecular orbitals involved in reactions of tropone illustrate that a repulsive secondary orbital interaction likely destabilizes the endo transition state, leading to complete selectivity for exo products. ref Mukherjee, D. Watts, C. R. Houk, ... more details
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