Über die Kristallstruktur von (C6H5)3SiSH und (C6H5)3SiSBr und die Darstellung des Iodsulfans (C6H5)3SiSI

The Crystal Structure of (C₆H₅)₃SiSH and (C₆H₅)₃SiSBr and the Preparation of the Iodosulfane (C₆H₅)₃SiSI The preparation of the halogenosulfanes Ph₃SiSBr and Ph₃SiSI from Ph₃SiSH and N-halogenosuccinimide is reported. They are characterized by vibrational spectroscopic measurements. Ph₃SiSBr crystallizes in space group P1 with a = 899.3(8) pm, b = 941.3(7) pm, c = 1 051.4(7) pm, α = 109.88(5)°, β = 99.23(6)°, γ = 96.78(6)° and Z = 2. Ph₃SiSH crystallizes in space group P2₁/c with a = 1 879.4(8), b = 966.3(5), c = 1 845.2(9), β = 107.84(4), Z = 8. The halogenosulfanes decompose in polar solvents by formation of sulphur and triphenylsilanhalide.     

Arylzinc alkoxides: [ArZnOCHPr(i)2]2 and Ar2Zn3(OCHPr(i)2)4 when Ar = C6H5, p-CF3C6H4, 2,4,6-Me3C6H2, and C6F5

From the reactions between diarylzinc compounds (Ar2Zn) and the alcohol (Pr(i)2CHOH) in toluene, the compounds [ArZn(OCHPr(i)2)]2 (Ar = C6H5, C6F5, p-CF3C6H4, and 2,4,6-Me3C6H2) have been isolated and shown to exist in equilibra with the trinuclear complexes Ar2Zn3(OCHPr(i)2)4 and Ar2Zn when Ar = C6H5, C6F5, and p-CF3C6H4. The trinuclear complexes have also been prepared from reactions of the Ar2Zn compounds with the alcohol, which reveals that the ease of Zn-C(aryl) bond cleavage is sensitive to the nature of the Ar group: C6H5 > 4-CF3C6H4 > C6F5. The molecular structures of Ar2Zn3(OCHPr(i)2)4 where Ar = p-CF3C6H4 and C6F5 and [ArZn(OCHPr(i)2)]2 where Ar = C6F5, p-CF3C6H4, and 2,4,6-Me3C6H2 are reported based on single-crystal X-ray diffraction studies. The X-ray structure of Zn(p-CF3C6H4)2 is also reported. The reactivity of these new compounds toward the polymerization of propylene oxide (PO) and the copolymerization of PO and CO2 have been investigated along with related reactions involving the partial hydrolysis of the Ar2Zn and R2Zn compounds, where R = t-Bu, n-Bu, and n-Oct. These results are compared with the previous studies employing Et2Zn as an organozinc precursor.     

The preparation,characterization and reactivity of the cyclometallosilane,cyclo-1,1-di-h5-cyclopentadienyltitana-2,2,3,3,4,4,5,5,-octaphenylpentasilane, (h5-C5H5)2TiSi(C6H5)2[Si(C6H5)2]2Si(C6H5)2

Titanium has been incorporated into a catenated silicon ring by means of the salt elimination reaction of dichlorodi-h⁵-cyclopentadienyltitanium(IV), (I), with 1,4-dilithiooctaphenyltetrasilane, Li₂Si₄(C₆H₅)₈, to yield the title compound (II). II was characterized as a cyclometallopolysilane by means of elemental analyses, base catalyzed hydrolyses, molecular weight determination, infrared and ¹H NMR spectroscopy. Electronic spectral data and electrochemical data are also discussed and support the formulation of II as a disubstituted (h⁵-C₅H₅)₂Ti^IV derivative. The reactivity of II, with CHCl₃, is described in terms of a radical decomposition pathway.     

Über die Darstellung der Bis(triphenylsilyl)-sulfane (C6H5)3Si?Sx?Si(C6H5)3 (x = 3, 4) und die Kristallstruktur von (C6H5)3Si?S4?Si(C6H5)3

On the Preparation of Bis(triphenylsilyl)sulfanes (C₆H₅)₃Si? S_x? Si(C₆H₅)₃ (x = 3, 4) and the Crystal Structure of (C₆H₅)₃Si? S₄? Si(C₆H₅)₃ The preparation of the bis(triphenylsilyl)sulfanes Ph₃Si? S_x? SiPh₃ (x = 3, 4) from Ph₃SiSNa and SCl₂ resp. S₂Cl₂ is reported. They are characterized by vibrational, NMR and UV-VIS spectroscopic measurements. Ph₃Si? S₄? SiPh₃ crystallizes in space group P1 with a = 943.6(6) pm, b = 945.7(5) pm, c = 1 881.7(12) pm, α = 82.11(5)°, β = 78.95(5)°, γ = 83.15(5)° and Z = 2.     

Kinetics of Polymerization of 1,3-Dioxolan Initiated by C6H5COSbF,and (C6H5)3C+SbF8 Salts

Polymerizations of 1,3-dioxolan initiated by oxycarbenium salt CeHsCO⁺SbFe^? and triphenylmethylium salt (C6H₅)₃C⁺SbF₆ ^? proceed with induction periods. C₆H₅CO⁺SbF6 initiates polymerization by a direct addition, while initiation with (C₆H₅CO⁺SbFe^?proceeds through the intermediately formed 1,3-dioxolan-2-ylium salt. Kinetic analysis of polymerization of 1,3-dioxolan, initiated by oxycarbenium salt or triphenylmethylium salt revealed that, in spite of different chemisty of initiation, both processes proceed with a slow initiation on monomer and fast initiation on polymer. The pertinent kinetic equations were derived and it was found, that the rate constant of propagation (k) does not depend on the structure of initiator used, being equal to 25 ± 5 liter/mole-sec (0°C, CH₂Cl₂ or CH₃NO₂).     

(C_5H_9C_5H_4)_3NdBrLi(THF)_3和(C_5H_9C_5H_4)_3SmTHF的合成与结构

无水三氯化钕与环戊烷基环戊二烯钠、溴化锂(1:2:1摩尔比)反应,除去不溶物和溶剂后,产物在己烷/四氢呋喃溶剂中冷冻得到兰紫色晶体(C5H9C5H4)3NdBrLi(THF)3(配合物1)。其中心金属Nd3+的配位数为10,以η5与3个环戊二烯基相连,并通过单溴原子桥连锂原子,形成双核结构。该晶体属三斜晶系,P`1空间群。晶体学参数为a=12.048(2)、b=13.498(3)、c=13.831(3);α=104.16(3)、β=104.07(3)、γ=95.96(3); V=2083.3(7)3、Z=2、Dc=1.35Mg/m3、Mr=847.01gmol-1、F(000)=874。无水三氯化钐与环戊烷基环戊二烯钠(1:3)反应,产物在-30oC下的己烷溶剂中结晶得桔红色晶体(C5H9C5H4)3SmTHF(配合物2)。该晶体属正交晶系,Fdd2空间群。晶胞参数a=28.175(5) 、b=46.24(2)、c=9.167(4);V=11943(8)3、Z=16、Dc=1.38Mg/m3、 Mr=622.11 g·mol-1、F(000)=5136。10配位的金属Sm3+与3个环戊二烯基以η5相连,并结合一个四氢呋喃溶剂分子。     

Molecular structure of (1–5,o-η-diphenylfulvene) chromium tricarbonyl [C5H4C(C6H5)2]Cr(CO)3

Journal of Structural Chemistry -     

Zur disproportionierung der phenylfluorphosphane (C6H5)2PF und (C6H5)PF2

Ph₂P-PF₂Ph₂ has been identified by means ¹⁹F- and ³¹P- NMR spectroscopy as an intermediate product of the disproportionation of Ph₂PF. The disproportionation is catalyzed by acids. The reaction mechanism is discussed. PhPF₂ disproportionates faster in solution in acetonitrile than neat, forming (PhP)₆, instead of (PhP)₅.