TY - JOUR A1 - Markgraf, J. H. A1 - Cort, J. R. A1 - Davis, H. A. A1 - Lindeman, N. I. A1 - Myers, C. R. A1 - Kraft, A. A1 - Christl, Manfred T1 - Strained Heterocyclic Systems. 20. Basicities of Bicyclic Quinoxalines N2 - No abstract available KW - Organische Chemie Y1 - 1991 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-58584 ER - TY - JOUR A1 - Christl, Manfred A1 - Reuchlein, H. T1 - Synthesis and NMR Spectra of 2,3-Dihydro-1,3-methanoindene Derivatives and 1,2,3,5-Tetrahydro-1,3-methanopentalene N2 - No abstract available KW - Organische Chemie Y1 - 1990 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-58557 ER - TY - JOUR A1 - Kim, E. A1 - Christl, Manfred A1 - Kochl, J. K. T1 - Charge-Transfer Cycloaddition of Homobenzvalene with Tetracyanoethylene N2 - The transient yellow color observed in the cycloaddition of homobenzvalene (HB) with tetracyanoethylene (TCNE) is associated with the charge-transfer complex [HB, TCNE). The deliberate photoexcitation of [HB,TCNE) affords a mixture of charge-transfer cycloadducts (1, 2, and 3) that differs from that obtained in thermal cycloaddition. The relationship of {HB t TCNE•) radical-ion pair (as the critical reactive intermediate in charge-transfer cycloaddition) to the activation process for thermal cycloaddition is discussed. KW - Organische Chemie KW - Electron transfer KW - photochemical KW - Radical-ion pair KW - Photochemistry Y1 - 1990 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-58537 ER - TY - JOUR A1 - Christl, Manfred A1 - Braun, Max T1 - Photocycloadditions of Benzvalene N2 - No abstract available KW - Organische Chemie Y1 - 1989 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-58506 ER - TY - JOUR A1 - Christl, Manfred A1 - Brunn, E. A1 - Roth, W. R. A1 - Lennartz, H.-W. T1 - 7-Methyl- and 7-Phenylcyclohepta-1,3,5-trienes from Benzvalene Via 3,3a,4,5,6,6a-Hexahydro-4,5,6-methenocyclopentapyrazoles and Tetracyclo[4.1.0.0\(^{2,4}\).0\(^{3,5}\)]heptanes N2 - No abstract available KW - Organische Chemie Y1 - 1989 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-58471 ER - TY - JOUR A1 - Christl, Manfred A1 - Kraft, A. T1 - Tricyclo[3.1.1.0\(^{2,6}\)]hexandion (the Valen of o-Benzochinons), Bicyclo[2.1.1]hexan-2,3-dion and Valene of a Chinoxalins, of Phenazins and of a Benzophenazine N2 - No abstract available KW - Organische Chemie Y1 - 1988 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-58462 ER - TY - JOUR A1 - Christl, Manfred A1 - Freund, S. A1 - Henneberger, H. A1 - Kraft, A. A1 - Hauck, J. A1 - Irngartinger, H. T1 - Several Polycyclic Valence Isomers of Dimethyl [14]Annulene-1,8-dicarboxylate. Reactivity of a "Nonconjugated" Bis(bicyclo[1.1.0]butane) N2 - Diels-Alder reaction of dimethyl 1,2,4,5-tetrazine-3,6-dicarboxylate (5) with benzvalene (4), norbornene, and norbornadiene afforded the azo compounds 7 and 8. Theseare derivatives of 2,3-diazabicyclo[2.2.2]oct-2-ene as is azo compound 3, which had been obtained previously from 5 and 2 equiv of benzvalene (4). The photochemical extrusion of nitrogen from 3, 7, and 8 has been studied. Whereas 7 and 8 on direct irradiation in benzene gave rise exclusively to the bicyclo[2.2.0]hexane derivatives 9 and 10, respectively, from 3 in addition to the bicyclo[2.2.0]hexane 11, the diolefin 1l was formed. Diolefin 12 has cisdouble bonds in the nine-membered ring and is fixed in a boat conformation in a manner so that the two bicyclobutane systems approach each other very closely. This geometry suggests the unusual ring opening of the intermediate 1,4-cyclohexanediyl diradical from a boat conformation, which arises by inversion of the primarily generated boat conformation. Sensitized photolysis of 3 as weilasthat of ll produced the saturated isomer 13 of 11 and 12. The proximity of the bicyclobutane systems in 1l causes unprecedented reactions leading to cage compounds. When ll was heated at 90 °C, a rearrangement to the pentacyclic product 10 took place. Utilization of tetradeuteriated substrate ll-d4 supported a pathway with two diradical intermediates. Behaving in a convcntional manncr, bicyclobutane 9 and bis(bicyclobutane) 11 took up 1 and 2 equiv of thiophenol most probably in a radical-chain addition to give the thioethers 28 and 19, respectively. In contrast, bis(bicyclobutane) ll was converted by 1 equiv of thiophenol into cagc compound 30 in a process involving both the strained a systems. Heating at 80 °C subjected 30 to a reversible Copc rearrangement, resulting in a 6:1 mixture of 31 and 30. When it was treated with bromine, 11 was transformed to cage compound 38. This addition is believed to proceed via a cationic intermediate. The structure of cage compound 10 was established by a singlc-crystal X-ray analysis of dialcohol 11 prepared from 20 and methyllithium. KW - Organische Chemie Y1 - 1988 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-58413 ER - TY - JOUR A1 - Korth, H.-G. A1 - Müller, W. A1 - Sustmann, R. A1 - Christl, Manfred T1 - Rearrangement of Free Radicals, XII. ESR Spectroscopic Study of the Ring Opening of the Homobenzvalenyl Radical N2 - Abstraction of an allylic hydrogen atom in homobenzvalene (4) either in solurion by photolyticaßy generated tert-butoxyl radicals or in an adamantane matrix by X-rays produces the homobcnzvalenyl radical (5). which tbennally rearranps · to tbe tropylium ndical (1). In solution tbe activation cnergy for the rate determined step of the reaction sequence was detennined· to be 13.4 ± O.S kcal/mol. KW - Organische Chemie Y1 - 1987 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-58376 ER - TY - JOUR A1 - Christl, Manfred A1 - Lang, R. A1 - Herzog, C. T1 - The Synthesis of Octavalene (Tricyclo[5.1.0.0\(^{2,8}\)]octa-3,5-diene) and Several Substituted Octavalenes N2 - No abstract available KW - Organische Chemie Y1 - 1986 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-58254 ER - TY - JOUR A1 - Leininger, H. A1 - Lanzendörfer, F. A1 - Christl, Manfred T1 - Über die Reduktion des Benzvalenozonids zum cis-1,3-Cyclobutandimethanol mit LiAlH\(_4\) N2 - No abstract available KW - Organische Chemie Y1 - 1983 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-58130 ER - TY - JOUR A1 - Christl, Manfred A1 - Lang, R. T1 - Tricyclo[5.1.0.0\(^{2,8}\)]octa-3,5-diene (Octavalene) N2 - No abstract available KW - Organische Chemie Y1 - 1982 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-58124 ER - TY - JOUR A1 - Christl, Manfred A1 - Herbert, R. T1 - Unusual Carbon Shielding Effects of Cyclopropanes and Double Bonds in Strained Bicyclo[3.1.0]hexanes and Cyclopentenes N2 - Carbon-13 shieldings and one-bond \(^{13}\)C-H coupling constants of bicydo[2.1.1]hexane, bicydo[2.l.l]hex- 2-ene, tricydo[3.1.1.0\(^{2.4}\)]heptane and benzvalene are presented and compared. to the data of related. compounds. H a bicydo[3.1.0]hexane system is part of a rigid skeleton, the cydopropane ring exerts spedfk: 'Y substituent eflects of two ldnds. In the case of the bicyclobexane boat form an upfield shift of the C-3 signal is observed and in tbe esse of the chair form a downfield shift of 15-20 ppm. Compared to the corresponding cydopentanes the double bond in strained cydopentenes causes downfield shifts of the C-4 absorption. 1bis eftect increases witb increasing strain, reaching 8 45.9 ppm maximum in benzvalene. Hence it is tbe only known bicydo[l.l.O]butane baving 8 reversed order of carbon shieldings. The downfield shifts are e:xplained by means of simple orbital interaction schemes. KW - Organische Chemie Y1 - 1979 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-58038 ER - TY - JOUR A1 - Volz, H. A1 - Shin, J.-H. A1 - Prinzbach, H. A1 - Babsch, H. A1 - Christl, Manfred T1 - Stability of Tricyclo[4.1.0.0\(^{2,7}\)]heptenyl-Cations N2 - No abstract available KW - Organische Chemie Y1 - 1978 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-58001 ER - TY - JOUR A1 - Christl, Manfred A1 - Heinemann, U. A1 - Kristof, W. T1 - Thermal Rearrangement of Some Endo-Endo'-Bridged Bicyclo[1.1.0]butanes N2 - No abstract available KW - Organische Chemie Y1 - 1975 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-57967 ER - TY - JOUR A1 - Christl, Manfred A1 - Warren, J. D. A1 - Hawkins, B. L. A1 - Roberts, J. D. T1 - \(^{13}\)C and \(^{15}\)N Nuclear Magnetic Resonance Spectroscopy of Nitrile Oxides and Related Reaction Products : Unexpected \(^{13}\)C and \(^{15}\)N Nuclear Magnetic Resonance Parameters of 2,4,6-Trimethylbenzonitrile Oxide N2 - No abstract available KW - Organische Chemie Y1 - 1973 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-57894 ER - TY - JOUR A1 - Christl, Manfred A1 - Roberts, J. D. T1 - Nuclear Magnetic Resonance Spectroscopy : Carbon-13 Chemical Shifts of Small Peptides as a Function of pH N2 - No abstract available KW - Organische Chemie Y1 - 1972 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-57885 ER - TY - JOUR A1 - Christl, Manfred A1 - Reich, H. J. A1 - Roberts, J. D. T1 - Nuclear Magnetic Resonance Spectroscopy. Carbon-13 Chemical Shifts of Methylcyclopentanes, Cyclopentanols, and Cyclopentyl Acetates N2 - No abstract available KW - Organische Chemie Y1 - 1971 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-57862 ER - TY - JOUR A1 - Gleiter, Rolf A1 - Bischof, Peter A1 - Gubernator, Klaus A1 - Christl, Manfred A1 - Schwager, Luis A1 - Vogel, Pierre T1 - 2,3-Bis(methylene)bicyclo[2.1.1]hexane and 3,4-Bis(methylene)tricyclo[3.1.0.0\(^{2,6}\)]hexane : Interaction between a π System and a Cyclobutane or Bicyclobutane Moiety N2 - The He (I) photoelectron spectra of 2-bicyclo[2.1.l]hexene (1), 2,3-bis(methylene)bicyclo[2.1.l]hexane (3), and 3,4-bis(methylene)tricyclo[3.l.O.0\(^{2.6}\)]hexane (4) have been investigated. The assignment given is based on a ZDO model and semiempirical calculations. Tagether with the PE data of benzvalene (2), the reported data allow a comparison between 1-2 and 3-4. This yields a measure of the interactions between 8 cyclobutane or 8 bicyclobutane moiety and a double bond system within a ZDO model. The resonance integral found in the case of 1 and 3 amounts to -1.9 eV, that for 2 and 4, to -2.3 eV. The investigations furthermore reveal that the electronic factors which contribute to the higher reactivity of the bicyclobutane compounds amount to 5 kcal/mol. KW - Chemie Y1 - 1985 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-31845 ER - TY - JOUR A1 - Christl, Manfred A1 - Schreck, Michael T1 - 1,2,3,5,8,8a-Hexahydronaphthalin aus 1,2-Cyclohexadien N2 - Reaktionen von 1,3-Butadien und einigen seiner Methylderivate mit 1a und 1- Methyl-1,2-cyclohexadien 1b sowie den Übergang der [2 + 2]-Cycloaddukte 2 und 3 in das bisher unbekannte 1,2,3,5,8,8a-HexahydronaphthaJin 4a und einige seiner Methylderivate KW - Chemie KW - Butadien Y1 - 1987 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-31656 ER - TY - JOUR A1 - Gleiter, Rolf A1 - Bischof, Peter A1 - Christl, Manfred T1 - Electronic Structure of Octavalene : Photoelectron Spectroscopic Investigations N2 - The He I photoelectron (PE) spectra of octavalene (5) as weil as its hydrogenated products 6-8 have been investigated. The assignment given is based on an empirical comparison of 5-8 with related compounds, a ZDO model, and semiempirical and ab initio calculations. Within the ZDO model the interaction between the buta.diene moiety and the bicyclobutane fragment of 5 is described by a resonance integral of -2.3 eV. The orbitalsequence of 5 is found tobe 2a\(_2\) (\(\pi\)-\(\sigma\)), 9a\(_1\) (\(\sigma\)), 3b1 (\(\pi\) - \(\sigma\)), 1a\(_2\) (\(\sigma\) + \(\pi\)), 2b\(_1\) (\(\sigma\) + \(\pi\)). KW - Chemie KW - Octavalen KW - Photoelektron Y1 - 1986 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-31588 ER -