Reaction of the hydroxyamine 7-chloro-4-(hydroxyamino)quinoline with the triosmium cluster Os 3 -(CO) 10 (NCMe) 2 gave the complex (µ-H)Os 3 (CO) 10 (µ 2 -η 1 -O-C 9 H 6 N 2 Cl) (3), in which a new mode of µ 2 -η 1 -Ooximato ligand bridged two osmium centers by an oxygen atom. This complex was slowly converted to (µ-H)Os 3 -(CO) 10 (µ 2 -η 2 -ON-C 9 H 6 NCl) (4), where an aromatic C-H moiety in the µ 2 -η 2 -ON-oximatoquinoline group formed an unusual short intramolecular C-H‚‚‚O-N hydrogen bond and an intermolecular C-H‚‚‚OdC hydrogen bond simultaneously. The formation of the intramolecular hydrogen bond may provide a stabilization effect for the generation of the η 2 -ON complex 4 and a driving force for the transformation of 3 to 4.
Mithilfe theoretischer Vorhersagen der erforderlichen Struktureigenschaften wurde die Einschlussverbindung von 1‐Bromadamantan mit Thioharnstoff (siehe Bild) als dichroitischer Filter für die Polarisationsanalyse von Röntgen‐Strahlung entwickelt. Der lineare Dichroismus, den die Substanz mit Röntgen‐Strahlung zeigt, bestätigt ihre optimale Eignung für die gewünschten Anwendungen.
We report the application of a one-dimensional Patterson analysis of diffuse X-ray scattering from the 1,8diiodooctane/urea inclusion compound to obtain information on the intermolecular interaction between the iodine end groups of adjacent 1,8-diiodooctane guest molecules within the urea tunnel host structure in this inclusion compound. One aspect of the X-ray scattering from the guest component in this incommensurate inclusion compound comprises diffuse sheets perpendicular to the host tunnel axis, and we consider measurements of the intensity, I(l g ), obtained from one-dimensional scans perpendicular to the diffuse sheets in reciprocal space (each diffuse sheet is specified by integer l g ). The one-dimensional Patterson map constructed from I(l g ) has a dominant peak at ca. 3.94 Å, which is interpreted as the projection, on to the tunnel axis, of the intermolecular I‚‚‚I distance. This value of D z (I‚‚‚I) is shown to be consistent with a model in which the iodine end groups are in van der Waals contact with the I f I vector lying essentially parallel to the tunnel axis. We emphasize that this well-defined structural information has been obtained despite the substantial disorder in this system.
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Treatment of 3-phenylthio-2-sulfolene (1) with an equimolar proportion of butyllithium at -78 ·C in THF followed by addition of an electrophiIe gave the 2-substituted 3-phenylthio-2-sulfolenes (2). The deprotonation was found to proceed only at the vinylic C-2 position. Some of the 2-sulfolenes 2 underwent desulfonylation upon heating with base. Of particular interest was the conversion of 3-phenylthio-2trimethylsilyl-2-sulfolene (2h) to its 3-sulfolene isomer 6 by sequential addition of butyllithium and salicylie acid at low temperatures. The 3-sulfolene 6 was desuIfonylated by Kugelrohr distillation at ISO •C under vacuum to give (Z)-2-phenylthio-l-trimethylsilyl-l,3-butadiene (8). The regiochemistry of the Diels Alder reaction of this highly reactive diene 8 was found to be controlled by the phenylthio group, and the stereochemistry is endo addition. Diene 8 was oxidized to its sulfone derivative 12 which also underwent a stereospecific Diels-Alder reaction.
S3
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