@article{FunkenEngelsPeyerimhoffetal.1990,
  author    = {Funken, K. and Engels, Bernd and Peyerimhoff, S.D. and Grein, F.},
  title     = {Study of the hyperfine coupling constants of the moleculs NH<sub>2</sub>, NHD and ND<sub>2</sub>},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58875},
  year      = {1990},
  abstract  = {In the present paper we c:alculate tbe magnetic hyperfine couplina constants (hfcc) ai.ID and A11 of the ground states of the isotopes NH2, NHD and ND2 using truncated MR..CI methods. Differences from other theoretical methocls and shortoominp of the truncated Cl approach in calculating tlj10 are studied. Polarization effects wbich detennirae ailo. as weU as a simple model to describe the dipolar hfcc's, are discussed. All results are in. excellent aareement with experimental data. lt is shown that ab initio methods are able to obtain reliable values for otf-diaaonal values of A41 which are difficult to measure experimentaDy.},
  subject      = {Organische Chemie},
  language  = {en}
}
@article{LangHerzogStangletal.1990,
  author    = {Lang, R. and Herzog, C. and Stangl, R. and Brunn, E. and Braun, M. and Christl, Manfred and Peters, K. and Peters, E.-M. and Schnering, H. G. von},
  title     = {Reaktionen von Homobenzvalenen mit 4-Phenyl-3H-1,2,4-triazol-3,5(4H)-dion, Tetracyanethylen, Chlorsulfonylisocyanat und Schwefeldioxid. Einige konzertierte 1,4-Additionen an eine Vinylcyclopropan-Einheit},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58527},
  year      = {1990},
  abstract  = {No abstract available},
  subject      = {Organische Chemie},
  language  = {de}
}
@article{ChristlReuchlein1990,
  author    = {Christl, Manfred and Reuchlein, H.},
  title     = {Synthesis and NMR Spectra of 2,3-Dihydro-1,3-methanoindene Derivatives and 1,2,3,5-Tetrahydro-1,3-methanopentalene},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58557},
  year      = {1990},
  abstract  = {No abstract available},
  subject      = {Organische Chemie},
  language  = {en}
}
@article{ChristlLanzendoerferGroetschetal.1990,
  author    = {Christl, Manfred and Lanzend{\"o}rfer, U. and Gr{\"o}tsch, M. M. and Ditterich, E. and Hegmann, J.},
  title     = {Cycloadditionen von 1,3,4-0xadiazin-6-onen (4,5-Diaza-alpha-pyronen), 9 - 6-Oxo-5-phenyl-1,3,4-oxadiazin-2-carbons{\"a}ure-methylester - Synthese und Reaktionen mit Norbornen, Norbornadien, Cyclopropenen, Cyclobuten und Benzvalen},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58569},
  year      = {1990},
  abstract  = {No abstract available},
  subject      = {Organische Chemie},
  language  = {de}
}
@article{ChristlReuchlein1990,
  author    = {Christl, Manfred and Reuchlein, H.},
  title     = {Synthesen und NMR-Spektren von 2,3-Dihydro-1,3-methanoindenderivaten und 1,2,3,5-Tetrahydro-1,3-methanopentalen},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58549},
  year      = {1990},
  abstract  = {No abstract available},
  subject      = {Organische Chemie},
  language  = {de}
}
@article{EngelsPeyerimhoff1989,
  author    = {Engels, Bernd and Peyerimhoff, S.D.},
  title     = {Theoretical study of FC\(_2\)H\(_4\)},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58824},
  year      = {1989},
  abstract  = {Large-scale multireference configuration interaction (MRD-CI) calculations in a quite flexible AO basis are employed to study the energy hypersurface for the reaction intermediate FC\(_2\)H\(_4\) • The reaction F + C\(_2\)H\(_4\) -> FC\(_2\)H\(_4\) as weil as the 1,2 migration of the fluorine atom in FC\(_2\)H\(_4\) is investigated. In addition the rotation around the CC bond in the optimum conformation is studied. The absolute minimum in the potential energy is found for the asymmetric structure but the symmetric structure is also found to be stable with respect to the dissociation, so that a shuttling of the fluorine atom is in principle possible but highly unlikely because ( l) the activation energy is high ( II 5-130 kJ fmol) and the saddle point lies only 4(}-50 kJ jmol below the dissociation Iimit of F + C\(_2\)H\(_4\) and (2) the competitive motion, i.e., rotation around the CC axis, is nearly free (I 1-17 kJ/mol).},
  subject      = {Organische Chemie},
  language  = {en}
}
@article{EngelsPeyerimhoff1989,
  author    = {Engels, Bernd and Peyerimhoff, S.D.},
  title     = {The hyperfine coupling constants of the X\(^3\)Σ\(^-\) state of NH : Influence of polarization functions and configuration space on the description of spin polarization},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58832},
  year      = {1989},
  abstract  = {The hyperfine coupling constants for the \(^3\)Σ\(-\) ground state of the NH molecule are determined by configuration interaction calculations whereby the infl.uence of polarization functions as weil as of the configuration space on the spin polarization mechanism is analysed. The dipolar part Au(N) and Au(H) can be obtained very reliably without much computational effort (A .. (N) == -45·3 MHz and A"(H) = -62·3 MHz). The value for the isotropic contribution a1.., in the best AO basis and MRD-CI treatment is - 64·5 MHz for H and 16·6 MHz for nitrogen compared to the corresponding experimental quantities of -66 MHz and 19 MHz respectively. Their determination depends on a subtle balance of the lu, 2u and 3u shell correlation description, whereby the dominant contribution to a1..,(H) results from the 2u shell. It is shown that the often good agreement of a110 values with experiment in a small basis singledouble configuration interaction treatment results from a cancellation of two errors.},
  subject      = {Organische Chemie},
  language  = {en}
}
@article{EngelsPeyerimhoff1989,
  author    = {Engels, Bernd and Peyerimhoff, S.D.},
  title     = {Study of orbital transformations in configurational interaction calculation of hyperfine coupling in nitrogen and CH molecule},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58847},
  year      = {1989},
  abstract  = {Multi-reference configuration interaction calculations employing various orbital transformations are undertaken to obtain the isotropic hyperfine coupling constant a\(_{iso\) in nitrogen and a\(_{iso\) (H) in the CH molecule. The natural orbital (NO) basis is found to be more effective than the simple RHF-MO basis; the most obvious is a basis of spin natural orbitals (SNO). It is found that a\(_{iso\) is approached from opposite sides in the NO and 2s shell SNO basis if the CI expansion is increased. Both results are within a few percent of the full CI Iimit for the nitrogen atorn (in the given AO basis) and the experimental value for Hin the CH radical. Various features ofthe SNO are discussed.},
  subject      = {Organische Chemie},
  language  = {en}
}
@article{KarnaGreinEngelsetal.1989,
  author    = {Karna, S. and Grein, F. and Engels, Bernd and Peyerimhoff, S.D.},
  title     = {The hyperfine coupling constants of \(^{19}\)F\(_2\)},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58817},
  year      = {1989},
  abstract  = {The isotropic (a\(_{iso}\)) and dipolar (A\(_{dip}\)) hyperfine coupling constants of 19F2 were obtained from MRD-CI wave functions using a variety of basis sets. In series I, increasing numbers of d functions were added to a 5s4p contracted Huzinaga!Dunning basis. In series II, the 5s3p basis set was uncontracted in several steps until 9s5p was reached, to which were added from one to three d-polarization functions. Cl parameters (selectioo threshoids and the number of reference coofiguratioos) were also varied. A study of the R dependence of aiso and Adip was perfonned. The best values obtained at R\(_e\) are 260 G for a\(_{iso}\) and 308 G for A\(_{dip}\)• compared with experimental values of about 280 G for a;10 and 320 G for A\(_{dip}\)·},
  subject      = {Organische Chemie},
  language  = {en}
}
@article{ChristlBrunnRothetal.1989,
  author    = {Christl, Manfred and Brunn, E. and Roth, W. R. and Lennartz, H.-W.},
  title     = {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},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58471},
  year      = {1989},
  abstract  = {No abstract available},
  subject      = {Organische Chemie},
  language  = {en}
}
@article{ChristlBrunnKraftetal.1989,
  author    = {Christl, Manfred and Brunn, E. and Kraft, A. and Irngartinger, H. and Huber-Patz, U.},
  title     = {Nichtbindende Wechselwirkungen in zwei 7-Spirotetracyclo[4.1.0.0\(^{2,4}\).0\(^{3,5}\)]heptanen},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58489},
  year      = {1989},
  abstract  = {Die Reaktion von Tetrachlordiazocyclopentadien mit Be.nzvalen (2) ergab das Fulven-Derivat 3. Dagegen f{\"u}hrten die Umsetzungen von Diazoßuoren und 5-Diazo-10,1 1-dihydro-SH-dibenzo[ a.d]cyclohepten mit 2 zu den erwarteten Spiro-1-pyrazolinen 4 bzw. 5. Die photolytische Abspaltung von Stickstoff aus 4 und 5 lieferte die Spirotetracycloheptane 6 bzw. 7. Die R{\"o}ntgenstrukturanalyse von 6 beweist einen engen Kontakt zwischen je eineßl Wasserstoffatom der Tetracycloheptan- und der Fluoren-Einheit. Dieser kurze Abstand (2.15 A) ruft Winkelaufweitungen hervor und wird auch als Grund f{\"u}r starke Entschirmungen der betreffenden Protonen und eine formal {\"u}ber sieben Bindungen reichende 0.6-Hz-Kopplung zwischen ihnen angesehen. 7 ist das erste chiralc Tetracyclohcptan. Ursache daf{\"u}r ist eine nichtebene Konformation des Siebenrings, der bei Raumtemperatur nicht invertiert. Auf der Basis von NOE-Messungen gelang die Zuordnung der tH-NMR-Signale von 6 und 7.},
  subject      = {Organische Chemie},
  language  = {de}
}
@article{ChristlBraun1989,
  author    = {Christl, Manfred and Braun, Max},
  title     = {Photocycloadditionen des Benzvalens},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58492},
  year      = {1989},
  abstract  = {No abstract available},
  subject      = {Organische Chemie},
  language  = {de}
}
@article{ChristlBraun1989,
  author    = {Christl, Manfred and Braun, Max},
  title     = {Photocycloadditions of Benzvalene},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58506},
  year      = {1989},
  abstract  = {No abstract available},
  subject      = {Organische Chemie},
  language  = {en}
}
@article{ChristlBraun1989,
  author    = {Christl, Manfred and Braun, Martin},
  title     = {Freisetzung und Abfangreaktionen von 1-Oxa-2,3-cyclohexadien},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58517},
  year      = {1989},
  abstract  = {Umsetzung von 6,6-Dichlor-2-oxabicyclo[3.1.0)hexan (4a) in Styrol mit n-Butyllithium lieferte neben Polystyrol und t-Chlor-1- pbenylhexan (6) in geringer Ausbeute die Tet~hydrocyclobutapyrane 5, die Abfangprodukte des aus 4a generierten t-Oxa-2,3- cyclobexadiens (3). Das unbest{\"a}ndige 6,6-Dibrom-2-oxabicyclo( J.l.O]hexan (4b) wurde bei -60°C erzeugt un~ bei -30°C mit Methyllithium in Gegenwart von Styrol umgesetzt, woraus die Produkte 5 mit 24\% Ausbeute hervorgingen. Als bei 20°C best{\"a}ndige Quelle f{\"u}r 3 erwies sich exo-6-Brom-e~o-6-fluor-2-oxabicyclo[ J.t.O]bexan (9), das aus 2,3-Dihydrofuran und Bromßuorcarben mit 25\% Ausbeute bereitet wurde. Behandlung von 9 in Styrol, <X-Methylstyrol, 1,3-Butadien, 2,3-Dimet~yl-!,3-butadien, Furan und 2,5-Dimethylfuran mit Methyllithium ergab Abfangprodukte von 3 mit Ausbeuten von 31-80\%. Dabei entstanden mit den Styrolen und {\"u}berwiegend auch mit den l ,3-Butadienen (2 + 2]-Cycloaddukte als Diastereomerengemische, n{\"a}mlich 5, ll, 13 und 15. Die Furane lieferten ausschließlieb [4 + 2]-Cycloaddukte (17 und 18), die 1,3-Butadiene nur mit einem kleinen Anteil (14 und 16). [2 + 2]- und [4 + 2]-Cycloadditionen zeigen eine unterschiedliche Chemoselektivit{\"a}t. W{\"a}hrend erstere die Enolether- Doppelbindung von 3 nutzen, finden letztere an der vom Sauerstoffatom entfernteren Doppelbindung statt. Das als 1 : IGemisch aus exo- und endo-Isomeren anfallende Produkt 5 lieferte beim Erhitzen auf l50°C ein 20:1: 1-Gemiseh aus exo- und endo-5 sowie dem Strukturisomeren 19. Thermolyse· des 2: 1-Gemisches aus 13 und 14 erbrachte ein 2: 1-Gemiscb aus 14 und dem Tetrahydro-1-benzopyran 20.},
  subject      = {Organische Chemie},
  language  = {de}
}
@article{HegmannChristlPetersetal.1988,
  author    = {Hegmann, Joachim and Christl, Manfred and Peters, Karl and Peters, Eva-Maria and Schnering, Hans Georg von},
  title     = {Die Reaktionskaskade von 6-Oxo-5-phenyl-1,3,4-oxadiazin-2-carbons{\"a}ure-methylester und 1,3-Butadienen zu konjugierten und nichtkonjugierten Cyclopentenonen},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58421},
  year      = {1988},
  abstract  = {F{\"u}nfgliedrige Carbocyclen sind Bauelemente zahlreicher NaturstofTe und daher attraktive Syntheseziele. Da bisher kein Syntheseverfahren mit großer Anwendungsbreite bekannt ist, sind neue Methoden willkommen. Wir berichten hier {\"u}ber Umsetzungen des Titelheterocyclus 1 mit l,3-Butadienen 1; diese Reaktionen, obwohl vielstufig, liefern im Eintopfverfahren konjugierte und nichtkonjugierte Cyclopentenone und gestatten auch die F{\"u}nfringanellierung.},
  subject      = {Organische Chemie},
  language  = {de}
}
@article{EngelsPeyerimhoff1988,
  author    = {Engels, Bernd and Peyerimhoff, S.D.},
  title     = {Study of the 1s and 2s shell contributions to the isotropic hyperfine coupling constant in nitrogen},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58793},
  year      = {1988},
  abstract  = {The istropic part of the hyperfine coupling constant is investigated by means of multireference configuration interaction calculations employing Gaussian basis sets. A detailed study of the 1s and 2s spin polarisation in the nitrogen atom and the NH molecule shows that the structure of the lower-energy space of the unoccupied orbitals is essential for the results. A contraction of the Gaussian basis is possible without loss of accuracy if enough flexibility is retained to describe the main features of the original space of unoccupied functions. Higher than double excitations are found to be non-negligible for the description of α\(_{iso}\).},
  subject      = {Organische Chemie},
  language  = {en}
}
@article{EngelsPeyerimhoffKarnaetal.1988,
  author    = {Engels, Bernd and Peyerimhoff, S.D. and Karna, S.P. and Grein, F.},
  title     = {The hyperfine coupling constants of the five lowest states of CH : An ab initio MRD-CI study},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58807},
  year      = {1988},
  abstract  = {No abstract available},
  subject      = {Organische Chemie},
  language  = {en}
}
@article{FreundHennebergerChristl1988,
  author    = {Freund, S. and Henneberger, H. and Christl, Manfred},
  title     = {Halbk{\"a}figverbindungen aus Diels-Alder-Addukten des Benzvalens mit Cyclopentadien-Derivaten durch Radikalreaktionen mit Thiophenol und Bromtrichlormethan},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58435},
  year      = {1988},
  abstract  = {In Diels-Alder-Reaktionen wurden aus Benzvalen (1) und Tetrachlorcyclopentadienon- dimethylacetal sowie Tetrachlorfuran die Addukte 2 bzw. 8 und 9 erhalten. Behandlung von 2 mit Natrium und tert-Butylalkohol ergab das chlorfreie Acetal 3, dessen Doppelbindung sich mit Diimin unter Bildung von 4 abs{\"a}ttigen ließ. Aus dem bekannten Stammkohlenwasserstoff 5 ging analog 6 hervor, und durch Reaktion seines Anions mit Chlorameisens{\"a}ure- methylester entstand der Ester 7. - Die Verbindungen l, 3, 5, 7-9 und das bekannte U wurden mit Thiophenol so behandelt, daß Radikalkettenreaktionen abliefen. Bei 8 trat Addition an die Zentralbindung des Bicyclobutan-Systems ein. Dagegen unterlag bei 2, 9, U und zum Teil bei 3, deren Doppelbindung jeweils der BicycJobutan-Einheit benachbart ist, das Prim{\"a}rradikal der 5-Hexen-1-yl- Cyclopentylrneth.yl-Umlagerung, aus der letztlich 15, ll, 13 bzw. 16 resultierten. Zum Teil bei 3 und vollst{\"a}ndig bei 5 erfolgte die Addition an die Doppelbindung zu 17 bzw. 18, d.h. ohne Beteiligung der benachbarten Bicyclobutan- Einheit. Durch Aktivierung des Bicyclobutan-Systems mit einer Esterfunktion konnte dessen Passivit{\"a}t aufgehoben werden. So entstanden aus 7 das nichtumgelagerte Produkt 19 und das umgelagerte 20. Ihr Verh{\"a}ltnis hing von der Konzentration an Thiophenol ab. - Analog zur Reaktion 1Z + Thiophenol-13 brachte BromtrichJormethan aus 12 das umlagerte Addukt 21 hervor. - Als Nebenprodukt wurde bei der Umsetzung von 12 mit Thiophenol das Chlorwasserstoff-Addukt 14 des ersteren gefunden. Modellreaktionen f{\"u}r die Bildung von 14 sind die Umsetzungen von 12 mit Essigs{\"a}ure und von 3 sowie 5 mit +Nitrobenzoes{\"a}ure zu den Addukten 22, 23 bzw. 24. Seit},
  subject      = {Organische Chemie},
  language  = {de}
}
@article{ChristlHennebergerFreund1988,
  author    = {Christl, Manfred and Henneberger, H. and Freund, S.},
  title     = {Halbk{\"a}figverbindungen aus Polycyclen mit einem Bicyclo[1.1.0]butan-System und dazu benachbarter Azobr{\"u}cke durch Radikalreaktionen mit Thiophenol und Bromtrichlormethan},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58440},
  year      = {1988},
  abstract  = {Aus Benzvalen (J) und 3,6-Bis(2-pyridyl)-l,2,4,5-tetrazin wurde das Dihydropyridazin 2c erhalten, das ebenso wie die bekannten Dihydropyridazine 2a, b mit Cyclopropen in die entsprechende Azoverbindung 3 {\"u}berging. Addition von Thiophenol an 3a, c und 5 lieferte unter Beteiligung des Bicyclobutan-Systems und der Azofunktion die Halbk{\"a}figverbindungen 4a, c bzw. 6. Aus der Umsetzung von 7, in dem die Azobr{\"u}cke durch zwei BicycJobutan- Systeme flankiert ist, mit Thiophenol sowie Bromtrichlormethan gingen die Halbk{\"a}figverbindungen 8 bzw. 9 hervor. An diesen ~eaktionen wirken beide Bicyclobutan-Systeme und die Azofunktion mit.},
  subject      = {Organische Chemie},
  language  = {de}
}
@article{ChristlKraft1988,
  author    = {Christl, Manfred and Kraft, A.},
  title     = {Tricyclo[3.1.1.0\(^{2,6}\)]hexandion (das Valen des o-Benzochinons), Bicyclo[2.1.1]hexan-2,3-dion und Valene eines Chinoxalins, des Phenazins sowie eines Benzophenazins},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58459},
  year      = {1988},
  abstract  = {No abstract available},
  subject      = {Organische Chemie},
  language  = {de}
}
@article{ChristlKraft1988,
  author    = {Christl, Manfred and Kraft, A.},
  title     = {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},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58462},
  year      = {1988},
  abstract  = {No abstract available},
  subject      = {Organische Chemie},
  language  = {en}
}
@article{ChristlFreundHennebergeretal.1988,
  author    = {Christl, Manfred and Freund, S. and Henneberger, H. and Kraft, A. and Hauck, J. and Irngartinger, H.},
  title     = {Several Polycyclic Valence Isomers of Dimethyl [14]Annulene-1,8-dicarboxylate. Reactivity of a "Nonconjugated" Bis(bicyclo[1.1.0]butane)},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58413},
  year      = {1988},
  abstract  = {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.},
  subject      = {Organische Chemie},
  language  = {en}
}
@article{ChristlNusserHerzog1988,
  author    = {Christl, Manfred and Nusser, R. and Herzog, C.},
  title     = {4-Bromoctavalen und zwei (Brommethylen)homobenzvalene anstelle eines erwarteten Bromoctabisvalens},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58409},
  year      = {1988},
  abstract  = {No abstract available.},
  subject      = {Organische Chemie},
  language  = {de}
}
@article{EngelsPeyerimhoffDavidson1987,
  author    = {Engels, Bernd and Peyerimhoff, S.D. and Davidson, E.R.},
  title     = {Calculation of hyperfine coupling constants : An ab initio MRD-CI study for nitrogen to analyse the effects of the basis sets and CI parameter},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58784},
  year      = {1987},
  abstract  = {The hyperfine coupling constant for the nitrogen atom is evaluated by large-scale MRD-CI calculations. A detailed analysis of the charge density at the nucleus and the spin polarization in the ls and 2s shell as a function of various technical parameters is undertaken. Various (s, p) AO basis sets and the inftuence of correlation orbitals is investigated as weil as selection threshold and other properlies in CI calculations. The best value, obtained for the isotropic hyperfine coupling constant in an s, p, d basis, based on theoretical judgment of' best' quantities, is 9·9 MHz compared to 10·4509 MHz.},
  subject      = {Organische Chemie},
  language  = {en}
}
@article{ChristlHerzog1987,
  author    = {Christl, Manfred and Herzog, C.},
  title     = {3-(Phenylsulfonyl)tricyclo[4.1.0.0\(^{2,7}\)]hept-4-en-3-yllithium},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58340},
  year      = {1987},
  abstract  = {Phenyl(tricyclo[4.1.0.0\^(^{2,7}\)] hept-4-en-3-yl)sulfone 8 has been prepared in two steps from 4,S-dlbromohomobenzvalene (6) and deprotonated to give the title compound 9. The carbon-13 NMR spectrum of 9 reveals a considerable interaction between the allyl anion moiety and the bicyclobutane system.},
  subject      = {Organische Chemie},
  language  = {de}
}
@article{ChristlSchreck1987,
  author    = {Christl, Manfred and Schreck, M.},
  title     = {7-Arylbicyclo[4.2.0]oct-1-ene - Synthese durch [2+2]-Cycloadditionen von 1,2-Cyclohexadien sowie 1-Methyl-1,2-cyclohexadien und thermische {\"A}quilibrierung der exo/endo-Isomeren},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58352},
  year      = {1987},
  abstract  = {Das exo/endo--lsomerenverh{\"a}ltnis Ja: Jb bei der bekannten [2 + 2]-Cycloaddition von Styrol an 1,2-Cyclohexadien (2) wurde als tempcraturabhingiaaefunden. Der Einsatz von (Z)-Dcutcriostyrollicfene den Beweis der Zweistufiakeit dieser Reaktion, und das Diradikal 4 wird als wahrscheinlichste Zwischenstufe anaesehen. Erhitzen von Jb auf 140-170°C f{\"u}hrte zur Binstellung des thermodynamischen Gleichgewichts mit Ja (Ja:3b = 93:7), wobei wieder das Diradikal4 als Zwischenstufe fungieren d{\"u}rfte. Mit Hilfe kinetischer Messungen ermittelte man die Aktivierungsparameter f{\"u}r das System Ja~ 3b. - Aus 2 und den Abfangreagenzien p-Methoxystyrol, 1,1-Diphenylethylen sowie 1-Phenylpropen gingen mit bescheidenen Ausbeuten die Titelverbindungen 6a, b, 7 bzw. 8 hervor. Analoa zu 2 wurde sein l-Methylderivat 13 aus 6,6-Dibrom-1-methylbicyclo[3.1.0]hexan (9) durch Methyllithium freigesetzt. In Gegenwart von Styrol entstand neben den Abfanaprodukten 14a, b auch das Dimere 12 von lJ. - Die 1H-NMR-Spektren der Titelverbindungen belegen eine starre Halbsesselkonformation des Cyclohexentcils mit {\"a}quatorial anellienem Cyclobutanring.},
  subject      = {Organische Chemie},
  language  = {de}
}
@article{KorthMuellerSustmannetal.1987,
  author    = {Korth, H.-G. and M{\"u}ller, W. and Sustmann, R. and Christl, Manfred},
  title     = {Rearrangement of Free Radicals, XII. ESR Spectroscopic Study of the Ring Opening of the Homobenzvalenyl Radical},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58376},
  year      = {1987},
  abstract  = {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.},
  subject      = {Organische Chemie},
  language  = {en}
}
@article{HegmannChristlPetersetal.1987,
  author    = {Hegmann, J. and Christl, Manfred and Peters, K. and Peters, E.-M. and Schnering, H. G. von},
  title     = {Intramolekulare [2+2]-Cycloadditionen von γ-Oxoketenen},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58384},
  year      = {1987},
  abstract  = {The 1-oxoketenes, which are accessible from methyl 1,3,4-oxadiazin-6-one-2-carboxyIate 1 and cycloalkenes, are shown to undergo an intramolecular [2+2] cycloaddition either on heating or on photolysis to give different sterecisemers of ß-lactones of the 3-oxo-2-oxabicyclo[ 2.2.0]hexane-type.},
  subject      = {Organische Chemie},
  language  = {de}
}
@article{ChristlHegmannReuchleinetal.1987,
  author    = {Christl, Manfred and Hegmann, J. and Reuchlein, H. and Peters, K. and Peters, E.-M. and Schnering, H. G. von},
  title     = {{\"U}berbr{\"u}ckte neungliedrige α,β-unges{\"a}ttigte Enollactone - Synthese aus 5-Phenyl-1,3,4-oxadiazin-6-on-2-carbons{\"a}ure-methylester und Konfigurationsanalyse},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58395},
  year      = {1987},
  abstract  = {The γ-oxoketenes, which are formed from oxadiazinone Ja and strained cyclopentene der1vat1ves, are shown to undergo a pericyclic ring enlargement to give the title compounds 2a, 2b, and 5. In the case of 5, two configurations, one having a cis and the other a trans Iactone functionality, are in equilibrium.},
  subject      = {Organische Chemie},
  language  = {de}
}
@article{ChristlHerzogBrueckneretal.1986,
  author    = {Christl, Manfred and Herzog, C. and Br{\"u}ckner, D. and Lang, R.},
  title     = {Neue Homobenzvalen-Derivate (Tricylo[4.1.0.0\(^{2,7}\)]hept-3-ene)},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58241},
  year      = {1986},
  abstract  = {No abstract available},
  subject      = {Organische Chemie},
  language  = {de}
}
@article{ChristlLangHerzog1986,
  author    = {Christl, Manfred and Lang, R. and Herzog, C.},
  title     = {The Synthesis of Octavalene (Tricyclo[5.1.0.0\(^{2,8}\)]octa-3,5-diene) and Several Substituted Octavalenes},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58254},
  year      = {1986},
  abstract  = {No abstract available},
  subject      = {Organische Chemie},
  language  = {en}
}
@article{ChristlMattauchIrngartingeretal.1986,
  author    = {Christl, Manfred and Mattauch, B. and Irngartinger, H. and Goldmann, A.},
  title     = {Additionen von Benzvalen an Nitriloxide. Eine Synthese f{\"u}r Benzvalen-3-carbonitril},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58269},
  year      = {1986},
  abstract  = {No abstract available},
  subject      = {Organische Chemie},
  language  = {de}
}
@article{ChristlKemmerMattauch1986,
  author    = {Christl, Manfred and Kemmer, P. and Mattauch, B.},
  title     = {1-Methylbenzvalen. Synthese und einige Reaktionen},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58270},
  year      = {1986},
  abstract  = {No abstract available},
  subject      = {Organische Chemie},
  language  = {de}
}
@article{EngelsPeyerimhoff1986,
  author    = {Engels, Bernd and Peyerimhoff, S. D.},
  title     = {Theoretical study of the bridging in β-Halo Ethyl},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58779},
  year      = {1986},
  abstract  = {Large-acale multi-reference configuration interaction (MRD-CI) calculations in a quite flexible AO basis are employed to study the energy hypersurface for the reaction intermediates XC\(_3\)H\(_4\) with X = Cl, Br and F. Particular emphasis is therby placed on determining the equilibrium conformations, the CH\(_2\) rotation barrier and the energy surface for a possible bridging (shuttling motion (1a] of X between the two carbon centers). The absolute minimum in the potential energy surface is found in all three cases for the asymmetric ß-halo radical in general agreement with ESR data at an XCC angle of ca. 110°, a c-c separation somewhat shorter than a single bond and an approximate sp3 type hybridization (\(\alpha _2 \approx \) 135-140°). In FC\(_2\)H\(_4\) the energy difference between the minimum in the symmetric conformation and the absolute minimum is found to be more than 30 kcal so that shuttling seems impossible in agreement with experimental findings. In BrC\(_2\)H\(_4\) the difference between these two potential minima is only between 1-2 kcal, i.e., smaller than the barrier to CH\(_2\), rotation, so that· shuttling is favored, while ClC\(_2\)H\(_4\) takes an intermediate position between these extremes. The use of correlated wavefunctions is found to be quite important for such a study; the results are related to various kinetic studies of these radicals.},
  subject      = {Organische Chemie},
  language  = {en}
}
@article{ChristlBrueckner1986,
  author    = {Christl, Manfred and Br{\"u}ckner, D.},
  title     = {Der Einfluß von Phenylgruppen auf die Homokonjugation im Bicyclo[3.2.1]octa-3,6-dien-2-yl-Anion. Eine \(^{13}\)C-NMR-Studie},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58288},
  year      = {1986},
  abstract  = {No abstract available},
  subject      = {Organische Chemie},
  language  = {de}
}
@article{HerzogLangBrueckneretal.1986,
  author    = {Herzog, C. and Lang, R. and Br{\"u}ckner, D. and Kemmer, P. and Christl, Manfred},
  title     = {Norpinene (Bicyclo[3.1.1]hept-2-ene) aus Homobenzvalenen (Tricyclo[4.1.0.0\(^{2,7}\)]hept-3-enen)},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58302},
  year      = {1986},
  abstract  = {No abstract available},
  subject      = {Organische Chemie},
  language  = {de}
}
@article{ChristlHerzogKemmer1986,
  author    = {Christl, Manfred and Herzog, C. and Kemmer, P.},
  title     = {Tricyclo[5.1.0.0\(^{2,8}\)]oct-3-en, -oct-4-en und -octan: Darstellung und Thermolyse der Hydroderivate des Octavalens},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58310},
  year      = {1986},
  abstract  = {No abstract available},
  subject      = {Organische Chemie},
  language  = {de}
}
@article{ChristlHerzogNusser1986,
  author    = {Christl, Manfred and Herzog, C. and Nusser, R.},
  title     = {Bicyclo[4.1.1]octa-2,4-dien, -oct-2-en, -oct-3-en und -octan aus Norpinen},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58326},
  year      = {1986},
  abstract  = {No abstract available},
  subject      = {Organische Chemie},
  language  = {de}
}
@article{ChristlHerzog1986,
  author    = {Christl, Manfred and Herzog, C.},
  title     = {\(^{13}\)C-NMR-Spektroskopie: Besondere Hochfeldeffekte in Bicyclo[4.1.1]- und Tricyclo[5.1.0.0\(^{2,8}\)]octan-Systemen (1,3-Cycloheptadien-Effekt) und besondere Tieffeldeffekte in Dihalogenbicyclo[2.1.1]hex-2-enen (Cyclopenten-Effekt)},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58334},
  year      = {1986},
  abstract  = {No abstract available},
  subject      = {Organische Chemie},
  language  = {de}
}
@article{ChristlFreund1985,
  author    = {Christl, Manfred and Freund, S.},
  title     = {Substituierte Benzobenzvalene und Diazabenzobenzvalene - Synthesen aus Diels-Alder-Addukten des Benzvalens und NMR-Spektroskopie},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58183},
  year      = {1985},
  abstract  = {No abstract available},
  subject      = {Organische Chemie},
  language  = {de}
}
@article{ChristlMattauch1985,
  author    = {Christl, Manfred and Mattauch, B.},
  title     = {Versuche zur Synthese eines formalen Nitriloxid-Addukts des Benzols. 1,3-Dipolare Cycloadditionen an Bicyclo[2.2.0]hex-5-en-2,3-dicarbons{\"a}ureanhydrid, Dewarbenzol und 1,4-Cyclohexadien},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58216},
  year      = {1985},
  abstract  = {No abstract available},
  subject      = {Organische Chemie},
  language  = {de}
}
@article{ChristlLanzendoerferGroetschetal.1985,
  author    = {Christl, Manfred and Lanzend{\"o}rfer, U. and Gr{\"o}tsch, M. M. and Hegmann, J.},
  title     = {Prim{\"a}raddukt, γ-Ketoketen und einige Folgeprodukte der Reaktion von 6-Oxo-5-phenyl-1,3,4-oxadiazin-2-carbons{\"a}ure-methylester mit Norbornen},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58220},
  year      = {1985},
  abstract  = {No abstract available},
  subject      = {Organische Chemie},
  language  = {de}
}
@article{ChristlLanzendoerferHegmannetal.1985,
  author    = {Christl, Manfred and Lanzend{\"o}rfer, F. and Hegmann, J. and Peters, K. and Peters, E.-M. and Schnering, H. G. von},
  title     = {Cycloadditionen von 6-0xo-l,3,4-oxadiazinen (4,5-Diaza-α-pyronen), 3 : Reaktionen von 6-Oxo-2,5-diaryl-1,3,4-oxadiazinen mit Alkenen},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58191},
  year      = {1985},
  abstract  = {Das bekannte 6-0xo-2,5-diphenyl-6H-l,3,4-oxadiazin (1 a) und die neuen 2,5-Diarylderivate 1 b - g lagern Alkene an, und es entstehen stickstofIfreie Produkte. Im Falle von Cyclopropenen und Cyclobuten bilden sich die a,p-unges{\"a}ttigten Siebenring-Enollactone 42 -45 bzw. das a,ß-unges{\"a}ttigte Achtring-Enollacton 47. 42a und d erleiden an basischem Aluminiumoxid die H-Verschiebung zu den ß,y-unges{\"a}ttigten Siebenring-Enollactonen 46a bzw. d. Bei weiteren Olefinen wurden die 'Y-Ketoketene des Typs 33 als Zwischenprodukte nachgewiesen oder sind aufgrund der Konstitution der Endprodukte wahrscheinlich. Aus 1 a werden mit Norbomen, Norbornadien, Cyc1openten, trans-Cycloocten und Styrol die Sechsring-Enollactone 10, 13, 15, 19 bzw. 21 und 22 erhalten. 10 isomerisiert mit Kalium-tert-butoxid zu 34, und die Methanolyse dieser Enollactone erbringt die diastereomeren Methy]ester 12 bzw. 35. Das y-Ketoketen 16 aus trans-Cycloocten nimmt schneller Wasser und Methanol zu 17 bzw. 18 auf als es zum Enollacton 19 cyclisiert. cis,trans-l,5-Cyc1ooctadien erbringt {\"u}ber die Stufe des nachgewiesenen y-Ketoketens 40 in einer intramolekularen [2 + 2J-Cyc1oaddition den Tricyclus 41. Tetracyclische Verbindungen des Typs 4 gehen aus der Umsetzung von Benzvalen (2) mit 1 hervor. Durch R{\"o}ntgenstrukturanalysen wurden Konstitution und Konfiguration von 10, 19 und 41 aufgekl{\"a}rt},
  subject      = {Organische Chemie},
  language  = {de}
}
@article{ChristlLangReimannetal.1984,
  author    = {Christl, Manfred and Lang, R. and Reimann, W. and Irngartinger, H.},
  title     = {Darstellung und R{\"o}ntgenstrukturanalyse des Diels-Alder-Addukts von 4-Phenyl-4H-1,2,4-triazol-3,5-dion an Octavalen},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58162},
  year      = {1984},
  abstract  = {No abstract available},
  subject      = {Organische Chemie},
  language  = {de}
}
@article{ChristlLeiningerKemmer1984,
  author    = {Christl, Manfred and Leininger, H. and Kemmer, P.},
  title     = {{\"U}ber das cis-Glycol und das Epoxid des Benzvalens},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58174},
  year      = {1984},
  abstract  = {No abstract available},
  subject      = {Organische Chemie},
  language  = {de}
}
@article{LeiningerLanzendoerferChristl1983,
  author    = {Leininger, H. and Lanzend{\"o}rfer, F. and Christl, Manfred},
  title     = {{\"U}ber die Reduktion des Benzvalenozonids zum cis-1,3-Cyclobutandimethanol mit LiAlH\(_4\)},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58130},
  year      = {1983},
  abstract  = {No abstract available},
  subject      = {Organische Chemie},
  language  = {en}
}
@article{LeiningerChristlWendisch1983,
  author    = {Leininger, H. and Christl, Manfred and Wendisch, D.},
  title     = {{\"U}ber die Oxidation von Benzvalen mit Singulett-Sauerstoff zum Bicyclo[1.1.0]butan-endo,endo-2,4-dicarbaldehyd},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58142},
  year      = {1983},
  abstract  = {No abstract available},
  subject      = {Organische Chemie},
  language  = {de}
}
@article{ChristlLanzendoerferPetersetal.1983,
  author    = {Christl, Manfred and Lanzend{\"o}rfer, F. and Peters, K. and Peters, E.-M. and Schnering, H. G. von},
  title     = {Die Reaktionen von 2,5-Diaryl-1,3,4-oxadiazin-6-onen mit trans-Cycloocten, cis,trans-Cyclooctadien und Cyclopropenen},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58156},
  year      = {1983},
  abstract  = {The transient [4+2]-cycloadducts from the title components eliminate nitrogen to form a 3,4-dihydro-2-pyrone derivative, a tricyclic cyclobutanone derivative and 2,5-dihydrooxepin-2-one derivatives, respectively.},
  subject      = {Organische Chemie},
  language  = {de}
}
@article{ChristlLechner1982,
  author    = {Christl, Manfred and Lechner, M.},
  title     = {Einige Reaktionen des 8,8-Dibromtetracyclo[5.1.0.0\(^{2,4}\).0\(^{3,5}\)]octans},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58108},
  year      = {1982},
  abstract  = {No abstract available},
  subject      = {Organische Chemie},
  language  = {de}
}
@article{LeiningerKemmerBecketal.1982,
  author    = {Leininger, H. and Kemmer, P. and Beck, K. and Christl, M.},
  title     = {7-Thiatetracyclo[4.1.0.0\(^{2,4}\).0\(^{3,5}\)]heptan (Benzvalensulfid) - Synthese und Reaktionen},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-58113},
  year      = {1982},
  abstract  = {No abstract available},
  subject      = {Organische Chemie},
  language  = {de}
}