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441.
Ferdinand R.W.P. Wild Laszlo Zsolnai Gottfried Huttner Hans H. Brintzinger 《Journal of organometallic chemistry》1982,232(3):233-247
A synthesis for racemic ethylene-bis(4,5,6,7-tetrahydro-1-indenyl)titanium dichloride is described. The molecular structures of this compound, of its meso- isomer and of a binaphtholate complex of the (S,S)-enantiomer have been determined. Cleavage of this binaphtholate complex gives the pure (S,tS)-enentiomer. 相似文献
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Ferdinand Bohlmann Christian-Herbert Fischer Jürgen Frster Wolfgang Mather Helmut Schwarz 《Journal of mass spectrometry : JMS》1975,10(12):1141-1146
The investigation of suitable model compounds shows that it is impossible to generalise about the mechanisms of the electron-impact-induced ‘Retro-Diels-Alder’ reaction on the basis of stereochemical effects. 相似文献
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447.
John H. Taylor Derek R. Harrison Ferdinand Fried 《Journal of heterocyclic chemistry》1972,9(6):1227-1228
Some new azepinoquinazolones were synthesized from 2-methyl-3(o-tolyl)-4(3H)quinazolone (metliaqualone )as potential hypnotic agents. Methaqualone (I) reacted with dimethyl acetylene-dicarboxylate (dmad) to give the azepinoquinazolone (II) which on treatment with PPA gave the pentacyclic ketone (V). Subsequent sodium borohydride reduction of the ketone (V) gave the fused azepine (VIa). Reaction of the azepinoquinazolone (II) with formic acid resulted in cleavage of the quinazolone nucleus to give the azepine (VIII). None of the compounds synthesized exhibited significant hypnotic activity. 相似文献
448.
Seebacher W Kröpfl D Belaj F Saf R Hüfner A Weis R 《Molecules (Basel, Switzerland)》2005,10(3):521-533
Benzylidene acetone reacts with thiocyanates derived from secondary amines in a one-pot reaction to give 4-aminobicyclo[2.2.2]octan-2-ones. The reaction mixture was investigated for the presence of possible intermediates using GC-MS. These intermediates - diketones and enamines - were prepared and exposed to the same reaction conditions to examine the reaction mechanism. The reaction of ethyl styryl ketone with thiocyanates of secondary amines yielded cyclohexanone derivatives instead of the expected bicyclo- octanones. Their structures were established by means of a single crystal structure analysis. 相似文献
449.
Synthesis, Crystal Structure and Electronic Band Structure of the Isostructural Sulfide Chlorides CuBiSCl2 and AgBiSCl2 Black, platelet crystals of MBiSCl2 (M = Cu, Ag) were synthesized by heating stoichiometric amounts of MCl and BiSCl. X‐ray diffraction on powders and single‐crystals revealed that the compounds crystallize isostructural with space group Cmcm (Cu/Ag: a = 396.9(1)/397.1(1); b = 1278.6(3)/1371.2(3); c = 859.7(2)/882.4(2) pm). In the crystal structures the BiIII cations have a bi‐capped trigonal prismatic coordination of two sulfide and six chloride ions. The polyhedra constitute layers equation/tex2gif-stack-2.gif[BiS2/2Cl6/3—] by sharing common edges and faces. The layers are separated by transition metal cations MI. Their distorted octahedral coordination comprises two short bonds M—S in trans position and four M—Cl bonds that are about 50 pm longer. From relativistic band structure calculations (DFT) is deduced that AgBiSCl2 is an indirect semi‐conductor with a band gap of about 1.0 eV. 相似文献
450.