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List of publications of Prof. Dr. H. J. Seifert  相似文献   

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SCF MO calculations have been made for Hafner's hydrocarbons using neglect of differential overlap after the manner ofPople andPariser andParr. * transitions have been calculated by a limited configuration interaction method. The results show that agreement between predicted spectra and observed spectra is quite good for the heptalene derivative and reasonably good for the pentalene derivative. It is suggested that both molecules are aromatic in contradiction to predictions by Craig's rule.
Zusammenfassung SCF MO-Rechnungen mit zero differential overlap nach der Methode vonPople, Pariser undParr wurden fürHafner's Kohlenwasserstoff angestellt. Mittels begrenzter Konfigurationswechselwirkung (wurden)die *-Übergänge berechnet, wobei die Ergebnisse im Fall des Heptalen-Derivates verhältnismäßig gut, in dem des Pentalen-Derivates jedoch nur ungefähr mit dem Experiment übereinstimmen. Darüber hinaus sprechen die Resultate im Gegensatz zur Craig'schen Regel dafür, daß beide Moleküle aromatischen Charakter haben.

Résumé Nous avons effectué des calculs SCF MO pour les hydrocarbures deHafner, en négligeant le recouvrement différentiel d'aprèsPople etPariser etParr. Quelques transitions * ont été calculées par interaction de configurations limitée. L'accord avec l'expérience est assez bon pour le dérivé de l'heptalène, et raisonable pour le dérivé du pentalène. Les deux molécules semblent être aromatiques, contrairement à la règle de Craig.
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This section contains news of the macromolecular community all over the world. Articles about, for example, people, projects, and market trends are welcome. Suggestions should be sent to the editorial office of the Macromolecular journals, preferably by E‐mail to macromol@wiley‐vch.de. The editorial office decides which articles will be published.  相似文献   

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The preparation of substituted pyridines from cycloalkanones by elaboration of an aromatic ring is described.  相似文献   

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The preparation of substituted phenols from cycloalkanones by elaboration of an aromatic ring is described.  相似文献   

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The molecular and crystal structure of dextromoramide has been determined by X-ray methods. The crystals are orthorhombic, space group P212121 with unit cell dimensions a = 9.720(4) A; b = 12.226(3) A; c = 18.381(3) A. The structure was determined by direct methods and the model refined to an R-value of 0.036 for 1788 observed reflections. The mean e.s.d.'s in bond lengths and angles are 0.004 A and 0.3, respectively. The morpholine moiety is nearly in antiposition relative to the quaternary carbon atom C6, the pertinent angle C6 - C7 - C9 - N2 being - 159.4. This conformation is similar to that previously reported for the bitartrate of the title compound. The pyrrolidine ring has the envelope conformation and the amide group is strictly planar. The conformation of some acyclic analgetics are discussed.  相似文献   

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Potassium superoxide is a selective oxidant for aromatic compounds with the order of susceptibility of substituent groups being -SH>-NH2-OH. Only o- and p- disubstituted amines and phenols are oxidized but monosubstituted thiols react.  相似文献   

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珠子参化学成分分析   总被引:6,自引:0,他引:6  
从珠子参根茎中分离得到7个化合物. 利用核磁共振、 质谱和红外等手段, 并结合其理化性质, 鉴定了其结构, 它们分别是24(R)-珠子参苷R1, 6-O-[β-D-吡喃葡萄糖基(1→2)-β-D-吡喃葡萄糖基]-20-O-[β-D-吡喃葡萄糖基(1→4)-β-D-吡喃葡萄糖基]-20(S)-原人参三醇、 6″-乙酰基-人参皂苷Rd、 人参皂苷Rf、 竹节参皂苷Ⅳa、 人参皂苷Rd和竹节参皂苷Ⅴ. 其中, 24(R)-珠子参苷R1和6-O-[β-D-吡喃葡萄糖基(1→2)-β-D-吡喃葡萄糖基]-20-O-[β-D-吡喃葡萄糖基(1→4)-β-D-吡喃葡萄糖基]-20(S)-原人参三醇为2个新化合物, 6″-乙酰基-人参皂苷Rd 和人参皂苷Rf为首次从珠子参根茎中得到.  相似文献   

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This paper gives complete details of a unique system for Magnetically Recording the Analogue Spectral Signals from an N.Q.R. Spectrometer of the S.R.O./Marginal Oscillator type.This is a very low cost system, but producing a very high order of play-back resolution from recordings, using a normal domestic Cassette or Tape, Reel to Reel Recorder. Spectra can also be transmisted via telephone lines, fibre optic links or radio frequencies.This system has been used now for several years, and due to the design being based mainly om passive components, the order of reliability is extremely high, without any faults being encountered to dete!.  相似文献   

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