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1.
The photoelectron(PE)spectrum of tricyclo[3.1.0.02,6] hex-2-ene(benzvalene 1) has been recorded. The first four bands in the PE spectrum of 1 can be assigned to transitions to 2B2, 2A1, 2A2 and 2B1 states of 11. This assignment is discussed in terms of the results of semiempirical and ab initio calculations on 1. Furthermore the highest occupied MO's of 1 are derived qualitatively from an interaction diagram between a distorted bicyclobutane and an ethylene moiety. 相似文献
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Peter Graf Ekkehard Kaempf Klaus Reichlmeier Karl Bernhard 《Helvetica chimica acta》1977,60(7):2151-2154
Metabolism of Acetylenic Monocarboxylic and Dicarboxylic Acids Feeding of acetylenic monoacids with chain length of 11 to 18 C-atoms to rats led to excretion of dicarboxylic acids with retained triple bonds. 10-Octadecynoic acid led to the formation of metabolites with even and odd number of C-atoms, suggesting in addition to established ω- and β-oxidation an α-oxidative pathway. 相似文献
4.
The pseudohalide CF3SO2NCO has been synthesized by means of a new reaction involving trifluoromethanesulphonamide and chlorosulphonylisocyanate. This method may be used for preparing other perfluorinated alkanesulphonyl-, arenesulphonyl- and alkanecarbonyl-amides. Reactions of CF3SO2NCO with alcohols, thiols, phenols and amines lead to the corresponding carbonic acid esters, thio-esters, phenyl esters and ureas. Reactions with carbonic acids, aldehydes and dimethylsulphoxide gave CO2 and the corresponding acid amides, azomethines and imino-dimethylsulphurane. Under pressure at 160°C, CF3SO2NCO reacts with phosphorus pentasulphide to give the previously unknown compound CF3SO2NCS; with phosphorus pentachloride under the same conditions, CF3SO2NCCl2 is formed. 相似文献
5.
The behaviour of tetraarylstannanes, R4Sn (R = C6H5CH2, C6H5, o-, m-, p-CH3C6H4), towards SO2 under various conditions has now been studied in detail. Compared to aliphatic tetraorganostannanes, the variability of the reaction products is much less, so that in nearly all cases only disulfinates, R2Sn(O2SR)2, are formed. The aromatic tin(IV) mono-, di- and tri-sulfinates are also obtained by metathetical reaction between the corresponding organotin halides and sodium sulfinates. A unique feature of triaryltin chlorides, R3SnCl (R = C6H5, o-, m-, p-CH3C6H4), is their disproportionation in liquid SO2 leading to disulfinates, R2Sn(O2SR)2, and dichlorides, R2SnCl2. (p-CH3C6H4)2SnCl2, under more efficient conditions, also accepts SO2 forming (p-CH3C6H4SO2)2SnCl2. The structural investigations of the newly prepared compounds are carried out on the basis of their IR and 1H NMR spectra. 相似文献
6.
Ekkehard Fluck Manfred Spahn Gernot Heckmann Horst Borrmann Axel Obermeyer 《Heteroatom Chemistry》1991,2(5):593-599
1,1,3,3 - Tetrakis(dimethylamino) - 1λ5,3λ5 - diphosphete, 1 , reacts with cyanoformic acid methyl ester to form two isomers of the title compound 2 . Properties, NMR, mass, and IR spectra of 2 , as well as the molecular and crystal structure of the E isomer of 2 , are described and discussed. 相似文献
7.
Mahmoud Sunjuk Mousa Al-Noaimi Ghassan Abu Sheikha Ekkehard Lindner Bassam El-Eswed Kamal Sweidan 《Polyhedron》2009
Water-soluble functionalized bis(phosphine) ligands L (a–h) of the general formula CH2(CH2PR2)2, where for a: R = (CH2)6OH; b–g: R = (CH2)nP(O)(OEt)2, n = 2–6 and n = 8; h: R = (CH2)3NH2 ( Scheme 1), have been prepared photochemically by hydrophosphination of the corresponding 1-alkenes with H2P(CH2)3PH2. Water-soluble palladium complexes cis-[Pd(L)(OAc)2] (1–8) were obtained by the reaction of Pd(OAc)2 with the ligands a–h in a 1:1 mixture of dichloromethane:acetonitrile. The water-soluble phosphine ligands and their palladium complexes were characterized by IR, 1H and 31P NMR. A crystallographic study of complex 1 shows that the Pd(II) ion has a square planar coordination sphere in which the acetate ligands and the diphosphine ligand deviate by less than 0.12 Å from ideal planar. 相似文献
8.
Ekkehard Krätzel 《Monatshefte für Mathematik》2002,137(3):197-211
In this article we investigate the number of lattice points in a three-dimensional convex body which contains non-isolated
points with Gaussian curvature zero but a finite number of flat points at the boundary. Especially, in case of rational tangential
planes in these points we investigate not only the influence of the flat points but also of the other points with Gaussian
curvature zero on the estimation of the lattice rest.
Received 19 June 2001; in revised form 17 January 2002
RID="a"
ID="a" Dedicated to Professor Edmund Hlawka on the occasion of his 85th birthday 相似文献
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