Synthese von Benzofuranen durch Cyclodehydrierung von Phenylmalonylheterocyclen

Phenylmalonyl heterocyclic compounds such as the quinolones1a–c or3, benzoquinolizinones6a, b and the phenalenones8a, b can be converted to benzofuranes (2a–c, 7a, b and9a, b) by cyclodehydrogenation with Pd/C in boiling diphenyl ether. 2-Phenylchinchonic acid (10) reacts under the same conditions to the dimeric benzofuroquinoline12: the decarboxylated quinoline11 however gives the monomer13.

Herrn Prof. Dr.G. Zigeuner zur Vollendung seines 60. Lebensjahres gewidmet.     

Spectral studies on the reaction of chromium (VI) compounds with aminophosphonic esters

The studies on reaction of newly obtained aminophosphonic acid diethyl ester derivatives of fluorene with Cr₂O₇ ^2–, CrO₄ ^2–, CrO₃Cl^– and CrO₃ have been investigated using electronic, infrared,Raman and NMR spectral methods. It has been found that the resulting compounds are of the type (AH)₂Cr₂O₇, whereA stands for the organic part of the molecule. The organic cation and solvent effects on the electronic states of pseudotetrahedrally arranged Cr(VI) anions are discussed.

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Spektroskopische Untersuchungen über Reaktionen von Chrom(VI)-Verbindungen mit Aminophosphonsäure-Estern

Zusammenfassung Es wurden Elektronen-, Ultrarot-,Raman- und NMR-spektroskopische Untersuchungen beschrieben, die an neuen Verbindungen durchgeführt wurden, welche als Reaktionsprodukte von Cr₂O₇ ^2–, CrO₄ ^2–, CrO₃Cl^– und CrO₃ mit Aminophosphonsäurediethylesterderivaten von Fluorene synthetisiert worden waren. Es wurde festgestellt, daß diese Verbindungen mit einer allgemeinen Formel (AH)₂Cr₂O₇ beschrieben können werden, in derA den organischen Teil der Verbindungen bedeutet. Der Einfluß des organischen Kations wie auch der von Lösungsmitteln auf die Elektronenzustände des pseudotetraedrischen Cr(VI)-Anions wurde gleichfalls untersucht.

     

Synthese von Propellanen aus 1,8-Dihydroxynaphthalin: 3,7,11,15-Tetraoxa[4,5,6-12,13,14-dinaphtho(1′,8′)]-(7.7.1)propellan

Condensation of 1,1,2,2,-tetrabromomethylcyclopropane with 1,8-dihydroxynaphthalene yielded the (7.7.1)-type propellane. The peri effect on the reaction and the product conformation is discussed. As a result condensation of 1,1-dibromomethylcyclopropane withperi-dihydroxynaphthalene gives the diether-type compound2 instead of the expected spirane2.

Jamrozik, J., Propellanes III. J. für prakt. Chemie, im Druck (1980).     

Studies on bisazocompounds I

The polarographic behaviour of the title compound in buffer solution ofpH 2–21 is discussed. The two observed waves in alkaline media (pH9.5) are assigned to the formation of hydrazo and the bishydrazo derivatives, whereas in acid solutions the reduction leads to cleavage of both two azo groups. The nature of the waves is investigated and a general mechanism for the reduction process in alkaline and acid media is suggested. The values of the kinetic parameters for the electrode reactions are reported.

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Untersuchungen an Bisazo-Verbindungen I. Polarographisches Verhalten von 1-[4-(4-Natriumsulfonato-phenylazo)-3-natriumsulfonato-phenylazo]-2-naphthol in Lösungen mit verschiedenem pH an der tropfenden Quecksilber-Elektrode Polarographic behaviour of 1-[4-(4-sodiumsulfonato-phenylazo)-3-sodiumsulfonato-phenylazo]-2-naphthol in solutions of varyingpH at the dropping mercury electrode

Zusammenfassung Es wird das polarographische Verhalten der Titelverbindung in Pufferlösungen vompH 2–12 diskutiert. Die zwei im alkalischen Bereich (pH9,5) beobachteten Wellen werden der Bildung der Hydrazo- bzw. Bishydrazo-Derivate zugeordnet, im sauren Bereich führt die Reduktion zur Spaltung beider Azo-Gruppen. Die Natur der Wellen wird untersucht, und ein genereller Mechanismus für die Reduktion im alkalischen und sauren Bereich wird vorgeschlagen. Die kinetischen Parameter der Elektrodenreaktionen werden angegeben.

     

Correlation of colour and crystal structure for silver(I) compounds

A geometrical analysis on 22 crystal structures of Ag(I) compounds with hard bases demonstrates that the observed colour-changes from colourless to red depend on the number of Ag(I) atoms coordinating the donor atoms of the base.

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Korrelation zwischen Farbe und Kristallstruktur in Silber(I)-VerbindungenKurze Mitteilung

Zusammenfassung Eine geometrische Analyse an 22 Kristallstrukturen von Ag(I)-Verbindungen mit harten Basen zeigt, daß sich die Farbe der Verbindungen mit steigender Anzahl von Silberatomen um die Donorzentren vertieft.

     

Darstellung von Organoquecksilber—Stickstoffverbindungen durch Synproportionierung

The exchange reaction ofR ₂Hg and >N–Hg–N< compounds yielding organomercury—nitrogen compounds may be widely applied, as shown here in the synthesis ofN-phenylmercury-amides,-imides,-heterocycles and-triazenes.

     

Die Schwingungsspektren einiger Pentadeuterophenylphosphorverbindungen

The vibrational spectra of C₆D₅PX ₂, (C₆D₅)₂PX (X=H, Cl), (C₆D₅)₃P and of the Cyclophosphanes (PC₆H₅) _n and (PC₆D₅) _n (n=5, 6) are reported. The spectra of the phenylphosphorouscompound D (the structure beeing unknown) are given too. The C₆H₅/C₆D₅ isotopic shift data in the lower frequency-region (600–100 cm^–1) (facilitating the recognition of vibrational coupling effects) are used for vibrational assignments.

     

Retention of Some Five-Membered Heterocyclic Compounds on a Porous Graphitized Carbon, Hypercarb™

The chromatographic performance of a Hypercarb^™ column was studied using some five-membered heterocyclic compounds. Significant retention of these molecules was observed with water/acetonitrile eluents. The influence of the organic modifier on retention was studied and interpreted on the basis of intermolecular interactions. The order of retention of solutes on Hypercarb^™ does follow their polarity order. Dispersion interactions undoubtedly have an influence, but do not determine the elution order of solutes. From the results obtained, it appears that the retention of the investigated substances is defined by interaction of polarized or polarizable functional groups in the samples with the graphite surface of the Hypercarb^™.     

Synthesen und Reaktionen von Pyridazinderivaten, 11. Mitt.: 5-Acyl-4-pyridazincarbonsäurrester als „key intermediates” für 4-Acylpyridazine und 4-Alkyl-bzw. 4-Arylpyridazino[4,5-d]pyridazin-1 (2H) one

A convenient general method of preparing 4-acylpyridazines (4) is reported. It involves homolytic acylation of ethyl-4-pyridazinecarboxylate yielding ethyl-5-acyl-4-pyridazinecarboxylates (2) which easily can be converted to4 by alkaline hydrolysis followed by decarboxylation. The hitherto unknown pyridazino[4,5-d]pyridazine-1 (2H) ones bearing an alkyl- or arylsubstituent on C-4 (5a-g) were prepared in quantitative yields by reaction of2 with hydrazine.

10. Mitt.:G. Heinisch, A. Jentzsch undI. Kirchner, Tetrahedron Lett.1978, 619.     

Vergleichende Reaktivitätsuntersuchungen am neuen Codimeren aus Malonitril und Cyanessigester an Carbonylverbindungen

The reactivity of 3-amino-2,4-dicyano-methyl-(1d) and-ethyl-crotonate (1e), resp., a new type of codimer from malononitrile and cyanoacetate, was investigated. Condensation reactions with aromatic aldehydes (2a-g), with heterocyclic aldehydes (2j-l), nitrosobenzenes (3a-c) ando-hydroxybenz-and-naphtaldehydes (4a-f), resp., are described, the differences in reactivity, compared with dimer malononitrile and dimeric forms of cyanoacetate (1a-c) are negligible. Condensation compounds of1a with cycloalkanones (5a-c) are able to cyclise with sulfur to cycloalkanonothieno-pyridines (6a-b), while the cycloalkano-derivatives of1d gave no ring closure.

Herrn Prof. Dr.O. E. Polansky zum 60. Geburtstag in Erinnerung an gemeinsame Tätigkeiten auf dem Gebiet der Nitrilchemie gewidmet.     

新型含氮杂环的酰基硫脲衍生物的合成

以取代苯甲酸为原料,经酰氯化和酰化反应制得取代苯甲酰基异硫氰酸酯(3);3与2-氨基-4-对硝基苯基噻唑经加成反应合成了5个含氮杂环的苯甲酰基硫脲衍生物,其中3个为新化合物,其结构经1H NMR,IR和元素分析表征。     

Berechnungen des Metathese-Gleichgewichtes zwischen Cyclopentenylverbindungen, 4-Octen und 4,9-Tridecadien-Derivaten

Empirical force field calculations are used to interpret the occurrence of cyclopentenyl compounds in the course of metathesis degradation of partially isomerized modified poly(1-butenylenes).

     

Komplexe von Acetylaceton und Acetonylaceton mit Alkali- und Erdalkaliionen. MO-SCF-Berechnungen und UV-Spektroskopie

In analogy to previous investigations on main group metal ion complexes with diacetyl², model calculations within the LCGO MO SCF framework using minimal basis sets are used in combination with UV spectrocopy in order to investigate complex formation tendencies, eventual ion specifities and ion binding energies of Li, Na, K, Mg and Ca ions with dicarbonyl ligands. The influence of the separation of the coordinative centers by methylene groups on the interaction with these metal ions is discussed. The simple quantum chemical models seem to work in the case of diacetyl and acetylacetone, whereas they fail in the prediction of the experimentally observed interaction of acetonylacetone with the metal ions.

     

Modelluntersuchungen zur Simulierung von LIS. II.1 2-, 3-und 7-substituierte 1-Indanone

The space close to the coordination site of1-indanone is modified systematically by placing alkyl groups of different bulkiness on C-2, C-3 and C-7, resp. The¹H-LIS for the compounds are interpreted using the one site and two site model for carbonyl. Precautionary measures are discussed for both models to give reliable results in the calculation.

Herrn Prof.O. E. Polansky mit den besten Wünschen zum 60. Geburtstag gewidmet.     

Compounds of oxozirconium(IV) alkoxides with oxygen and nitrogen bases

Pyridine, quinoline, 2,2-bipyridyl, dimethylformamide, dimethylacetamide and phthalimide combine with ZrOCl(OCHMe ₂)·2Me ₂CHOH to form complexes, ZrOCl(OCHMe ₂)·Base [with the exception of dimethylsulfoxide: Zr₂O₂Cl₂(OCHMe ₂)₂·3DMSO], whereas dialkoxides, ZrO(OR)₂·ROH (R=Me, Et, Pr ⁱ ), fail to react. The complexes have been characterized through infrared, molar conductance and thermal decomposition studies.

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Komplexe von Oxozirkonium(IV)-Alkoxiden mit Sauerstoff- und Stickstoff-Basen

Zusammenfassung Pyridin, Chinolin, 2,2-Bipyridyl, Dimethylformamid, Dimethylacetamid und Phthalimid geben mit ZrOCl(OCHMe ₂)·2Me ₂CHOH Komplexe vom Typ ZrOCl(OCHMe ₂)·Base [ausgenommenDMSO: Zr₂O₂Cl₂(OCHMe ₂)₂·3DMSO], während Dialkoxide, ZrO(OR)₂·ROH (R=Me, Et, Isopr), keine Reaktion ergeben. Die Komplexe wurden durch ihre IR-Spektren, molare Leitfähigkeit und mittels Untersuchung der thermischen Zersetzung charakterisiert.

     

Synthese homokonjugierter Polyene: 2,4-Dimethylenbicyclo[3.2.0]oct-6-en und 2,5-Dimethylenbicyclo[4.2.0]non-7-en

The synthesis of the two homoconjugated trienes has been achieved by cleavage of the strained -bonds of suitable cyclopropane and cyclobutane precursors. Ionization energies are discussed.

     

青风藤有效化学成分与环氧合酶的对接研究

将青风藤中23个有效化学成分与COX-2酶对接,有四个化合物具有较低的结合自由能,其中以青藤碱为最低.进一步将这四个化合物与COX-1酶对接,发现这四个化合物与COX-1酶结合能力较弱,预示这四个化合物具有选择性抑制COX-2酶的能力.对青藤碱和COX-2以及COX-1酶的结合模式进行分析,发现青藤碱主要结合于COX-2酶的S′口袋,而COX-1酶的S′结合口袋中第523号残基由COX-2酶中的Val523变成了体积较大的Ile523,使得COX-1酶的S′结合口袋相对COX-2酶的结合口袋要小,从而导致青藤碱分子不能进入COX-1酶S′结合口袋.这成功解释了青藤碱选择性抑制COX-2酶的原因,与早期有关文献报道的实验结果相吻合,充分表明了对接模型的合理性,青藤碱等化合物可作为设计COX-2酶选择性抑制剂的先导化合物.     

Die Darstellung der Oligosilane Si8 X 18 (X-Cl,OCH3) durch Photolyse von Silylquecksilberverbindungen

The formation of SiSi-bonds by a photochemical reaction of silylmercury compounds is described. The silylmercury compounds [(X ₃Si)₃Si]₂Hg (X=Cl, OCH₃) were synthesized via theVyazankin Hydrid method with (X ₃Si)₃SiH and Bis(t-butyl)mercury. By UV-irradiation of these products in hexane as a solvent, the oligosilanes [(X ₃Si)₃Si]₂ are formed in good yields. All these compounds are charactericed by spectroscopical methods.