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71.
By employing silver salts with a weakly coordinating anion Ag[A] ([A]=[FAl{OC12F15}3], [Al{OC(CF3)3}4]), two phosphaalkynes could be coordinated side‐on to a bare silver(I) center to form the unprecedented homoleptic complexes [Ag(η2‐P≡CtBu)2][FAl{OC12F15}3] ( 1 ) and [Ag(η2‐P≡CtBu)2][Al{OC(CF3)3}4] ( 2 ). DFT calculations show that the perpendicular arrangement in 1 is the minimum energy structure of the coordination of the two phosphaalkynes to a silver atom, whereas for 2 a unique square‐planar coordination mode of the phosphaalkynes at Ag+ was found. Reactions with donor molecules yield the trigonally planar coordinated silver salts [((CH3)2CO)Ag(η2‐P≡CtBu)2][FAl{OC12F15}3] ( 3 ) and [(C7H8)2Ag(η2‐P≡CtBu)][FAl{OC12F15}3] ( 4 ). All of the compounds were comprehensively characterized in solution and in the solid state.  相似文献   
72.
73.
The coordination behavior of [(Cp*Mo)2As2S3] (3) (Cp* = C5Me5) toward Cu(I) halides was investigated. One dimensional polymers of the general formula [(Cp*Mo)2As2S3(CuHal)2]n (Hal = Cl, 4; Br, 5) and an oligomer of composition [{(Cp*Mo)2As2S3}3(CuI)7] (6) formed upon the reaction of 3 with the corresponding copper halide. All of the compounds were characterized by ESI-MS, elemental analysis, and single-crystal X-ray crystallography. The solid-state structures of 4 and 5 are isostructural and contain 1D S-shaped chains. This peculiar folding is achieved by alternating planar and folded Cu2Hal2 rings linked together by the central monosulfide bridge of the middle deck of the organometallic unit. The structure of 6 is characterized by a novel [CuI]7 aggregate, which forms a very flat Cu6I3S3 bowl along with three integrated peripheral [(Cp*Mo)2As2S3] building blocks. In contrast to earlier findings, the middle deck of the organometallic units consists in all structures of two trapezoidal AsS dumbbells and one monosulfide ligand.  相似文献   
74.
75.
Reaction of tert -Butyl-phosphaalkyne with Molybdenum Complexes The reaction of tBuC≡P with [(CH3CN)3Mo(CO)3] leads to the complex [Mo(CO)4〈Mo(CO)24-P3CtBu){η4-P2(CtBu)2}〉] 1 as well as to the alkyne complexes [Mo(CO)4〈{P3(CtBu)2}{Mo(CO)2(CtBu)}{η3-P2(CtBu)2}〉] 2 and [Mo(CtBu){η4-P2(CtBu)2(CO)}{η5-P3(CtBu)2}] 3 . All compounds are characterized by X-ray structural analysis, by NMR- and IR spectroscopy and by mass spectrometry. In complex 1 a 1,3-diphosphacyclobutadiene and a 1,2,4-triphosphacyclobutadiene are connected by two molybdenum carbonyl centres. In 2 a 1,3-diphosphacyclobutadiene is π- and a novel 1,2,4-triphospholyl ligand is σ-bonded at two Mo centres. A characteristic feature of 3 besides a π co-ordinated 1,2,4-triphospholyl ligand is a 3,4-diphosphacyclopentadienone as ligand, formed via CO insertion during the cyclodimerisation of two phosphaalkynes.  相似文献   
76.
77.
The reaction pattern of the Lewis-acid/base stabilised phosphanylborane [(CO)5W(H2PBH2 · NMe3)] (1) with elemental halogens is comprehensively studied. The reaction with iodine and bromine leads to a selective halogenation at the tungstencarbonyl moiety under formation of [WX2(CO)4(H2PBH2 · NMe3)] (X = I (2), Br (3)). Whereas 2 is a stable product the brominated compound 3 dimerises easily to [WBr2(CO)3(H2PBH2 · NMe3)]2 (4) under lost of CO. The CO elimination reaction of 3 is extensively studied. If 3 is reacted with [Et4N][Br] the ionic compound [Et4N][WBr3(CO)3(H2PBH2 · NMe3)] (5) is formed. Otherwise, if 3 is combined with the donor ligand [H2PBH2 · NMe3], the complex [WBr2(CO)3(H2PBH2 · NMe3)2] (6) is obtained. Compounds 26 are comprehensively characterised by X-ray diffraction analysis, NMR, and IR spectroscopy.  相似文献   
78.
PAls should stick together : The cyclo‐trimer 2 is obtained by H2 elimination of Lewis acid/base‐stabilized parent compound of the phosphanylalanes 1 . The elimination is controlled by fine tuning the temperature and solvent conditions. A subsequent H2 elimination produces the ladder compound 3 . Compounds 2 and 3 are the first of a new class of Group 13/15 compounds which show no additionally donor–acceptor bonds within the framework.

  相似文献   

79.
Template‐controlled self‐assembly of discrete molecular pentaphosphaferrocene and CuCl units was used to form the first entirely carbon‐free molecule that has C80 topology and encapsulates a carborane unit. In their Communication on page 5046 ff. , M. Scheer and co‐workers report the synthesis and characterization of this impressive supramolecular compound, which displays an electronic interaction between the carborane and the spherical host molecule. C blue, Fe olive, P pink, Cl green, C gray, B/C orange, H white.

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80.
In the light of recent works by Fitchard and Mackinnon, experimental evidence by Nuttall and Gallon is interpreted as an indication of a violation of Heisenberg's uncertainty relation. Possible loopholes and their avoidance in future experiments are discussed.  相似文献   
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