XI 73)Sunzmary. The photoelectron spectra of quadricyclanc (3) and 3-methylidenc quadricyclane (4) havc becn measured. Thc results servcd as a basis for the clucidation of the electronic structurc of thesc compounds, which agrccd with theoretical calculations. It is found that the symmetry of the HOMO of 3 is different when compared to that of its valencc isomer norbornadiene (1). The results also indicate that the structure of the highest occupied orbitals cannot be derived by only coiisidcring the Walsh-orbitals of the two thrce-membered rings. In addition one of thc Walshcomponents of the four-membered ring has to be taken into account. 2Here we report on the orbital electronic structure of quadricyclane (3), and on that of a "key-compound" analogous to 2, 3-methylidene-quadricyclane (4).'0,The results are of importance in view of the valence-isomer relationship 1=3 as well as for an understanding of cycloadditions involving 3 (51. l) 'Small Ring Compounds', part 9. Part 8 , s. [l]
Die Synthese der bicyclischen Polyene 8 -11 gelang durch Spaltung der gespannten cr-Bindung der Dreiring-Dimethanole 14b/15 b bzw . der Vierring-Dimethanol-bis(methansu1fonate) 16c/17c mit P,I, bzw. Zn/KBr. Aus 'H-NMR-spektroskopischen Untersuchungen wird auf eine bevorzugte endo-Konformation fur 8 bzw. eine verdrillte Konformation fur 10 geschlossen. Das fur diese Geometrien erwartete AusmaR an transanularer Konjugation ist in Einklang mit den photoelektronen-spektroskopischen Ergebnissen. Synthesis of Bicyclic Non-conjugated Polyenes. Stereochemistry and Transanular Interactions1a)The synthesis of the bicyclic polyenes 8 -11 has been achieved by cleavage of the strained o-bonds of suitable cyclopropanedimethanols 14b/15b and cyclobutanedimethanol-bis(methanesu1fonates) 16c/17c using P,I, (14b/15b) or Zn/KBr (16c/17c), respectively. From an inspection of the 'H NMR spectra a preferred endo-conformation (chair) for 8 and a twisted structure (twist-chair) for 10 is proposed. The predicted extent of transanular conjugation for these geometries is in accordance with the photoelectron spectroscopic measurements.Wechselwirkungen zwischen nicht-konjugierten Doppelbindungen mit ein oder zwei Methylengruppen als formalen Isolatoren (Topologie 1 bzw. 2) sind von erheblicher Bedeutung fur die Reaktivitat oder spektroskopischen Eigenschaften dieser Polyene. Als typische Beispiele seien die Cyclisierung des Humulens (3)2,3) zu 4 und die Aufspaltung der ersten drei Ionisationspotentiale des Isopropylidennorbornadiens (5)4) genannt .
Among reported cases of abuse of volatile anesthetics there is only one of enflurane intoxication. We report another fatal enflurance intoxication. A 21-year-old man found dead seemed to have experimented with enflurane. Three and one-half days after death high amounts of enflurane were detected in blood, brain, and subcutaneous fat. Gas chromatographic quantification revealed the following high enflurane concentrations: blood: 130 mg/l−1, brain: 350 mg/l−1, and subcutaneous fat: 100 mg/l−1. Histologic signs of drug-induced damage were lacking. No suicide intentions became known. It was concluded that the young man died of an accidental intoxication while abusing enflurane.
Durch eine photoelektronenspektroskopische Untersuchung des Radikalkations des Methylenhomocuneans 8 in Verbindung mit den sterisch fixierten Bicyclopropylen 5, 6, 7 und 9 wird gezeigt, daB die vertikale Stabilisierung in den Radikalionen von 5 und 8 von vergleichbarer GroBenordnung ist (p z -0.3 eV). Der Unterschied in den Solvolysebeschleunigungen 17/18 (Faktor 20) und 3/1 (Faktor 10") kann deshalb nicht auf vertikale Stabilisierungseffekte zuriickgefiihrt werden, sondern demonstriert eindringlich die homoaromatische Stabilisierung in einem verzerrten, iiberbriickten ubergangszustand auf der Reaktionskoordinate zwischen 3 und 4.Vertical or Nonvertical Stabilization in the 9-Pentacycl0~4.3.0.0~ *'.@*8.@.']nonyl Cation?The 9-Methylenepentacyclononane Radical Cation') A photoelectron spectroscopic investigation of the radical cation of methylenehomocuneane 8, together with the sterically rigid bicyclopropyls 5, 6, 7 and 9, reveals a vertical stabilization of comparable order (B % -0.3 eV) in the radical cations of 5 and 8. The differences in solvolysis rate enhancements of 17/18 (a factor of 20) and 3/1 (a factor of lo'*) therefore cannot he accounted for by vertical Stabilization effects but demonstrate impressively the homoaromatic stabilization in a distorted bridged transition state on the reaction coordinate between 3 and 4.Die anchimere Beschleunigung der Solvolyse von 7-Norbornylderivaten durch endoanti-standige Dreiringe ist gut belegt. Dabei wurde die Beteiligung des Dreirings mit der Ausbildung stabiler Trishomocyclopropenylionen 4 (oder rasch aquilibrierender Aquivalente) erklart ').
Capsules with etryptamine have been commonly available on the market since the middle of 1985. Up to 1962 this CNS-stimulating, monoamine-oxidase-inhibiting drug was sold as an antidepressant (Monase). A case of fatal intoxication is reported. The exact amount of etryptamine taken several hours before death are not known, but it could have been in the range of 700 mg. This drug was detected in tissue by means of common analytical techniques (GLC, GC-MS, HPLC, TLC). Etryptamine cross-reacts with the Emit-st amphetamine assay and can also be detected in urine using these techniques. The level in postmortem blood was 1.1 mg/l. The effects the young man showed were like those known from intoxication with amphetamines, MAO inhibitors, and thymoleptics. Malignant hyperthermia is discussed as a possible cause of death. It is suggested that trade in etryptamine should be controlled.
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