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Jens Beckmann Dainis Dakternieks Andrew Duthie Naomi A. Lewcenko Cassandra Mitchell Markus Schürmann 《无机化学与普通化学杂志》2005,631(10):1856-1862
The reaction of (p‐MeOC6H4)2TeO with two equivalents of HO3SCF3 and HO2PPh2 provided the tetraorganoditelluroxanes (F3CSO3)(p‐MeOC6H4)2TeOTe(p‐MeOC6H4)2(O3SCF3) ( 1 ) and (Ph2PO2)(p‐MeOC6H4)2TeOTe(p‐MeOC6H4)2(O2PPh2)·2 Ph2PO2H ( 2 ) in good yields. Compounds 1 and 2 were characterized by solution and solid‐state 31P and 125Te NMR spectroscopy, IR spectroscopy, electrospray mass spectrometry, conductivity measurements and single crystal X‐ray diffraction. In solution, compound 1 undergoes an electrolytic dissociation and reversibly reacts with traces of water to give the mononuclear cation [(p‐MeOC6H4)2TeOH]+ and triflate anions. Theoretical aspects of the protonation and hydration of model telluroxanes R2TeO (R = H, Me, Ph) were investigated by preliminary DFT calculations and compared to the corresponding selenoxanes R2SeO. The tellurium dihydroxides R2Te(OH)2 seem to be more stable than the hydrogen‐bonded complexes R2TeO·H2O. 相似文献
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Michael Chariss Andrea Zickgraf Heike Stenger Elmar Bru Cristelle Desmarquet Martin Drger Silke Gerstmann Dainis Dakternieks James Hook 《Polyhedron》1998,17(25-26)
44 members of thecompound series Ph4−nMRn (M=Si, Ge, Sn, Pb; R=o-, m-, p-Tol; n=0–4) were synthesized (15 newcompounds). The crystal structures of Ph3Sn (o-Tol) and PhSn (o-Tol)3 were determined and compared to 16 known structures. Subject to the distanced (M–C), an interplay between through-space π–π repulsion and π–σ attraction leads to either elongated or compressed tetrahedral geometry. 29 Si-, 119 Sn- and 207 Pb-NMR chemical shifts were determined in solution and in the solid state. 73 Ge chemical shifts were measured only in solution. Anupfield or downfield sagging of the chemical shifts along each series is rationalized in terms of a π–σcharge transfer which is constrained by torsion of the aromatic groups. 相似文献
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The molecular structure of the title compound, obtained by an adventitious phenyl group cleavage of Ph3SnOSnPh3 with triflic acid, reveals discrete centrosymmetric units of [Ph2(HO)SnOSn(O3SCF3)Ph2]2 that are loosely associated via hydrogen bonding. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
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Dainis Dakternieks Andrew Duthie Douglas R. Smyth Clynton P. D. Stapleton Edward R. T. Tiekink 《应用有机金属化学》2003,17(12):960-960
The tin atom in the title compound is in a skew‐trapezoidal bipyramidal geometry defined by two sets of nitrogen and oxygen donors derived from the carboxylate ligands and two carbon atoms from the tin‐bound cyclopentyl substituents; C? Sn? C 153.38(16)°. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
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Jens Beckmann Klaus Jurkschat Stephanie Rabe Markus Schürmann Dainis Dakternieks 《无机化学与普通化学杂志》2001,627(3):458-464
The syntheses of the asymmetrically substituted tetraorganodistannoxanes [t‐Bu2(X)SnOSn(Y)(CH2SiMe3)2]2 ( 1 , X = Y = OH; 2 , X = Cl, Y = OH; 3 , X = Y = Cl) are reported and their structures in solution and in the solid state are characterized by multinuclear NMR spectroscopy and single crystal X‐ray analyses. In toluene, the tetrahydroxy‐substituted derivative 1 is in equilibrium with the organotin oxides cyclo‐[t‐Bu2Sn{OSn(CH2SiMe3)2}2O] ( 4 ), cyclo[(Me3SiCH2)2Sn(OSnt‐Bu2)2O] ( 5 ), and cyclo‐(t‐Bu2SnO)3, and some additional, undefined species containing pentacoordinated tin atoms. In contrast, the dihydroxydichloro‐substituted derivative 2 is inert in solution. 相似文献
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Dainis Dakternieks Andrew Duthie Douglas R. Smyth Clynton P. D. Stapleton Edward R. T. Tiekink 《应用有机金属化学》2004,18(1):53-54
The tin atom in the title compound is in a distorted pentagonal bipyramidal geometry defined by two sets of nitrogen and oxygen donors derived from the carboxylate ligands, two carbon atoms from the cyclohexyl substituents and an oxygen atom from the coordinated water molecule; C? Sn? C 170.85(15)°. Extensive hydrogen bonding occurs in the lattice. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
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Jens Beckmann Dainis Dakternieks Susan L Floate Carl H Schiesser 《Journal of organometallic chemistry》2004,689(5):909-916
The H2PtCl6 catalysed hydrosilylation of the terpenes (+)-α-fenchene (XI), (−)-2-methylene bornane (XII), (+)-camphene (XIII) and (−)-3-methylene fenchane (XIV) using HSiMe2Cl or HSiMeCl2 proceeds with high regioselectively and in some cases, with high diastereoselectivity. KF-assisted oxidation of the hydrosilylation products gives predominately endo-terpene alcohols. The alcohols have inverted endo/exo ratios to those formed by oxidative hydroboration. Reaction of XIV with HSiMe2Cl or HSiMeCl2 is accompanied by a clean rearrangement of the isocamphane skeleton into (+)-2-methylene bornane (XII) prior to hydrosilylation. 相似文献
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Jens Beckmann Dainis Dakternieks Andrew Duthie Edward R. T. Tiekink 《无机化学与普通化学杂志》2002,628(13):2948-2953
The six‐, eight‐ and twelve‐membered cyclo‐siloxanes, cyclo‐[R2SiOSi(Ot‐Bu)2O]2 (R = Me ( 1 ), Ph ( 2 )), cyclo‐(t‐BuO)2Si(OSiR2)2O (R = Me ( 3 ), Ph ( 4 )), cyclo‐R2Si[OSi(Ot‐Bu)2]2O (R = Me ( 5 ), Ph ( 6 )) and cyclo‐[(t‐BuO)2Si(OSiMe2)2O]2 ( 3a ) were synthesized in high yields by the reaction of (t‐BuO)2Si(OH)2 and [(t‐BuO)2SiOH]2O with R2SiCl2 and (R2SiCl)2O (R = Me, Ph). Compounds 1 — 6 were characterized by solution and solid‐state 29Si NMR spectroscopy, electrospray mass spectrometry and osmometric molecular weight determination. The molecular structure of 4 has been determined by single crystal X‐ray diffraction and features a six‐membered cyclo‐siloxane ring that is essentially planar. The reduction of 1 — 6 with i‐Bu2AlH (DIBAL‐H) led to the formation of the metastable aluminosiloxane (t‐BuO)2Si(OAli‐Bu2)2 ( 7 ) along with Me2SiH2 and Ph2SiH2. 相似文献