- On the reactivity of metal and organometallic halides toward r 3sn-o-snr3 systems
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Interaction of metallic salts (M = Hg, Sb, and Te) with bis(triorganotin) oxide, (R3Sn)2O, where (R = C6H5, p-CH3C6H4, and cyclo-C6H 11) at room temperature
- Singhal, Kiran,Mishra, Rahul,Raj, Prem
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experimental part
p. 278 - 283
(2010/02/27)
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- Tellurium tetrachloride: an improved method of preparation
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An efficient and practical synthesis of tellurium tetrachloride from elemental tellurium and sulfuryl chloride is described.
- Petragnani, Nicola,Mendes, Samuel R.,Silveira, Claudio C.
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p. 2371 - 2372
(2008/09/18)
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- Chalcogeno-Substituted Bis-triphenylmethylium Ions of the Inverse Malachite Green Type
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The longest wavelength VIS absorptions of the deeply colored CF3CO2H solutions of the 4,4'-chalcogenobis-(triphenylmethylium) ions 4(++), Y2 (Y = O, S, Se, Te) resemble closely those of the corresponding monocationic 4-arylchalcogenotriphenylmethylium systems 5(1+), ArYC6H4C(1+)(C6H5)2, and not those of the structurally directly related 4,4'-bis(arylchalcogeno)triphenylmethylium ions 3(1+), C6H5C(1+)(C6H4YAr)2.This is in striking contrast to the results obtained previously for analogous nitrogen systems, where "inverse", 2(++), RN, and "conventional" malachite green systems 1(+), (Ar2NC6H4)2C(1+)R, yield almost identical λmax values.A rationalization of these observations can be achieved based on the assumption of largely delocalized dications 2(++) versus more or less orthogonal "double monocationic" systems 4B(++), separated due to torsional twist.Whereas the formal push-pull systems 6(+), ArSC6H4YC6H4C(1+)(C6H5)2 (Y = O, S, Se) behaved practically like the corresponding standard systems 5(+), the mono- and bis-triphenylmethylthio-substituted dibenzofuran, dibenzothiophene and thioxanthene derivatives 8(+), 9(++), 10(+) and 11(++) displayed hypsochromic shifts of their color bands relative to their noncyclic analogues which are only partly in accordance with predictions based on a simple frontier orbital Hueckel model.The 1H and 13C NMR spectra of all these cationic species comply with their respective charges. +"--"+ Dyes, Chalcogeno-bis-trityliumions, VIS Spectra, NMR Spectra
- Hellwinkel, Dieter,Stahl, Heinz
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p. 521 - 538
(2007/10/02)
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