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161.
162.
Westenkirchner A Villinger A Karaghiosoff K Wustrack R Michalik D Schulz A 《Inorganic chemistry》2011,50(6):2691-2702
Differently substituted hydrazinophosphanes of the type (Me(3)Si)(2)N-N(SiMe(3))-PR(1)R(2) (R(1) = Cl with R(2) = Me, C(6)F(5) and R(1) = Me, R(2) = C(6)H(5)) have been studied in the reaction with Lewis acids such as ECl(3) (E = Al, Ga). For (Me(3)Si)(2)N-N(SiMe(3))-P(Cl)(Me) and (Me(3)Si)(2)N-N(SiMe(3))-P(Me)(C(6)H(5)), only adduct formation was found while a chlorine/methyl exchange reaction was observed for (Me(3)Si)(2)N-N(SiMe(3))-P(Cl)R (R = C(6)H(5) and C(6)F(5)) leading to the formation of (Me(2)ClSi)(Me(3)Si)N-N(SiMe(3))-P(Me)R, which crystallize as ECl(3) adducts. The free hydrazinophosphanes can be obtained by removal of the Lewis acid with the help of a strong base such as 4-(dimethylamino)pyridine (DMAP). 相似文献
163.
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165.
Omer Andac Yildiray Topcu Veysel T. Yilmaz Kutalmis Guven 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(12):1381-1384
The structures of the title triethanolamine (tea) complexes of CdII and HgII saccharinates, bis(triethanolamine)-κ3O,N,O′;κ4O,N,O′,O′′-cadmium(II) 1,2-benzisothiazol-3(2H)-onate 1,1-dioxide, [Cd(C6H15NO3)2](C7H4NO3S)2, (I), and bis(triethanolamine)-κ3O,N,O′;κ4O,N,O′,O′′-mercury(II) 1,2-benzisothiazol-3(2H)-onate 1,1-dioxide, [Hg(C6H15NO3)2](C7H4NO3S)2, (II), or [M(tea)2](sac)2, where M is CdII or HgII and sac is the saccharinate anion, reveal seven-coordinate metal ions in both complexes. Both complex cations, [M(tea)2]2+, adopt a monocapped trigonal prism geometry in which the two tea ligands exhibit different coordination modes to achieve seven-coordination. One tea ligand acts as a tetradentate ligand using all its donor atoms, while the other behaves as a tridentate O,N,O′-donor ligand, with one of its ethanol groups remaining uncoordinated. The H atoms of the free and coordinated hydroxyl groups of the tea ligands are involved in hydrogen bonding with the amine N atom, and with the carbonyl and sulfonyl O atoms of neighbouring sac ions, forming an infinite three-dimensional network. A weak π–π interaction between the phenyl rings of the sac ions also occurs. 相似文献
166.
Jrg Harloff Dirk Michalik Simon Nier Axel Schulz Philip Stoer Alexander Villinger 《Angewandte Chemie (International ed. in English)》2019,58(16):5452-5456
Starting from fluoridosilicate precursors in neat cyanotrimethylsilane, Me3Si?CN, a series of different ammonium salts [R3NMe]+ (R=Et, nPr, nBu) with the novel [SiF(CN)5]2? and [Si(CN)6]2? dianions was synthesized in facile, temperature controlled F?/CN? exchange reactions. Utilizing decomposable, non‐innocent cations, such as [R3NH]+, it was possible to generate metal salts of the type M2[Si(CN)6] (M+=Li+, K+) via neutralization reactions with the corresponding metal hydroxides. The ionic liquid [BMIm]2[Si(CN)6] (m.p.=72 °C, BMIm=1‐butyl‐3‐methylimidazolium) was obtained by a salt metathesis reaction. All the synthesized salts could be isolated in good yields and were fully characterized. 相似文献
167.
The existence of the weak limit as n of the uniform measure on rooted triangulations of the sphere with n vertices is proved. Some properties of the limit are studied. In particular, the limit is a probability measure on random triangulations of the plane. 相似文献
168.
Omer Sahin Fevzi Aslan Mustafa Ozdemir Mustafa Durgun 《Journal of Crystal Growth》2004,270(3-4):604-614
Growth rate of polycrystalline disc of borax compressed at different pressure and rotated at various speed has been measured in a rotating disc crystallizer under well-defined conditions of supersaturation. It was found that the mass transfer coefficient, K, increased while overall growth rate constant, Kg, and surface reaction constant, kr, decreased with increasing smoothness of the disc. It was also determined that kinetic parameters (kr,r,K,g) of crystal growth rate of borax decreased with increasing rotating speed of the polycrystalline disc. The effectiveness factor was calculated from the growth rate data to evaluate the relative magnitude of the steps in series bulk diffusion through the mass transfer boundary layer and the surface integration. At low rotating speed of disc, the crystal growth rate of borax is mainly controlled by integration. However, both diffusion and integration steps affect the growth rate of borax at higher rotating speed of polycrystalline disc. 相似文献
169.
Alexander Hinz Prof. Dr. Axel Schulz Dr. Alexander Villinger 《Angewandte Chemie (International ed. in English)》2015,54(2):668-672
Main‐group singlet biradicaloids have been thoroughly investigated in the past two decades, especially derivatives of cyclobutane‐1,3‐diyl. However, in each of the known examples, the radical centers are identical. Therefore, we sought to prepare a mixed dipnictadiazanediyls with P and As bearing the radical character. To achieve this goal, the unprecedented cyclodichloro arsaphosphadiazane [ClP(μ‐NTer)2AsCl] had to be prepared first. Treatment of [ClP(μ‐NTer)2AsCl] with a halide‐abstracting agent led to the novel cyclic cation [P(μ‐NTer)2AsCl]+, while reduction with magnesium afforded the first arsaphosphadiazanediyl [P(μ‐NTer)2As]. 相似文献
170.