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151.
A series of new bay region disphospha-functionalised naphthalenes is reported. The reduction of ylidic phosphonium phosphoride NapP(2)Cl(6) (1) (Nap=naphthalene-1,8-diyl) with MeOPCl(2) gives the important synthon Nap(PCl(2))(2) (2) in nearly quantitative yield. Reaction of 1 with magnesium metal affords (NapP(2))(n) (3), which reacts with Br(2) and I(2), yielding Nap(PBr(2))(2) (4) and Nap(PI)(2) (5), respectively. X-ray structure determinations reveal a twisted geometry of the naphthalene ring in sterically strained 2 and 4, whilst the presence of a P-P bond in 5 results in the release of the steric strain and generation of the planar NapP(2) moiety. Although the tetrahedral P environments are severely distorted the sigma(3)P-sigma(3)P bonding in 5 represents a new type of P-P bonding environment in 1,8-diphosphanaphthalenes. Compounds 1, 4 and 5 each represent the highest coordination, achievable by direct halogenation. The new compounds 2-5 were fully characterised by NMR, IR, and Raman spectroscopy, mass spectrometry, and elemental analysis. 相似文献
152.
Gibson VC Tellmann KP Humphries MJ Wass DF 《Chemical communications (Cambridge, England)》2002,(20):2316-2317
Bis(imino)pyridine cobalt(I) n-alkyl complexes react with ethylene by beta-hydrogen transfer, allowing direct study of a termination step commonly encountered in polymerisation and oligomerisation catalysis. 相似文献
153.
H. G. Kilian W. Schrodi F. Ania R. K. Bayer F. J. Baltá Calleja 《Colloid and polymer science》1991,269(9):859-866
The compressive stress-strain behavior of biaxially oriented polyethylene (PE), obtained by pressing uniaxially oriented samples, is described with the aid of the van der Waals equation of state. Results are discussed in terms of two parameters: the biaxiality (B) and the biaxial draw ratio (), which offer a measure of the strain along the two principal directions and of the average draw ratio on the film plane, respectively. Comparison of experimental and calculated data indicates that after compression up to very large deformations the maximum average strain (
m
), which is proportional to the square root of the chain length of the network, remains constant. This result supports the view that the network of entanglements is not destroyed after compression. Experiments carried out on isotropic melt crystallized PE show the presence of a network having a not very different chain length. Finally, it is shown that the segment length of this network is close to the X-ray long period of the initial structure. This result implies the existence of a high density of entanglements (two entanglements every three adjacent lamellae), which are rejected into the defective layer of the crystals. 相似文献
154.
Skwarnicki T Antreasyan D Besset D Bienlein JK Bloom ED Brock I Cabenda R Cartacci A Cavalli-Sforza M Clare R Conforto G Cooper S Cowan R Coyne D Edwards C Engler A Folger G Fridman A Gaiser J Gelphman D Godfrey G Heimlich FH Hofstadter R Irion J Jakubowski Z Keh S Kilian H Kirkbride I Kloiber T Koch W König AC Königsmann K Kraemer RW Lee R Leffler S Lekebusch R Litke AM Lockman W Lowe S Lurz B Marlow D Maschmann W Matsui T Messing F Metzger WJ Monteleoni B Nernst R Niczyporuk B Nowak G Peck C 《Physical review letters》1987,58(10):972-975
155.
Prof. Dr. Wolfgang Scherer M. Sc. Petra Meixner Dipl.‐Phys. Kilian Batke Dr. José E. Barquera‐Lozada Prof. Dr. Klaus Ruhland M. Sc. Andreas Fischer Dr. Georg Eickerling Dr. Klaus Eichele 《Angewandte Chemie (International ed. in English)》2016,55(38):11673-11677
We will outline that the sign and magnitude of J(Si,H) coupling constants provide a highly sensitive tool to measure the extent of Si?H bond activation in nonclassical silane complexes. Up to now, this structure–property relationship was obscured by erroneous J(Si,H) sign determinations in the literature. These new findings also help to identify the salient control parameters of the Si?H bond activation process in nonclassical silane complexes. 相似文献
156.
Sterically Congested 2,6‐Disubstituted Anilines from Direct C−N Bond Formation at an Iodine(III) Center
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Nicola Lucchetti Dr. Michelangelo Scalone Dr. Serena Fantasia Prof. Dr. Kilian Muñiz 《Angewandte Chemie (International ed. in English)》2016,55(42):13335-13339
2,6‐Disubstituted anilines are readily prepared from the direct reaction between amides and diaryliodonium salts. As demonstrated for 24 different examples, the reaction is of unusually broad scope with respect to the sterically congested arene and the nitrogen source, occurs without the requirement for any additional promoter, and proceeds through a direct reductive elimination at the iodine(III) center. The efficiency of the coupling procedure is further demonstrated within the short synthesis of a chemerin binding inhibitor. 相似文献
157.
Reaction of the triamido stannate MeSi[SiMe(2)N[(R)-CHMePh]](3)SnLi (1) with 0.5 molar equivalent of [RhCl(olefin)(2)](2) (olefin = COE, C(2)H(4)) or [RhCl(P(i)Pr(3))(2)](2) yielded the Rh-Sn complexes [MeSi[SiMe(2)N[(R)-CHMePh]](2)[SiMe(2)N[(R)-CHMe(eta(6)-C(6)H(5))]SnRh(L)] (L = COE: 2a, C(2)H(4): 2b, P(i)Pr(3) 3); their intramolecular eta(6)-coordination, along with the tin-rhodium bond, represents the first "ansa" pi-arene/stannate system. 相似文献
158.
W. Brückner B. Granz D. Ingham K. Kilian U. Lynen J. Niewisch B. Pietrzyk B. Povh H.G. Ritter H. Schröder 《Physics letters. [Part B]》1977,67(2):222-224
Annihilation and elastic cross-sections of p have been measured between 400 and 850 MeV/c. In both cross-sections a resonance is observed at a mass of 1939 ± 3 MeV. For its natural width τ ? 4 MeV is obtained. 相似文献
159.
Ohne ZusammenfassungHerrn Professor Dr.R. Hosemann zum 60. Geburtstag. 相似文献
160.